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fred/series/observations

Description

Get the observations or data values for an economic data series.

Examples

This request can return either XML, JSON, zipped tab delimited text, or a zipped Excel spreadsheet by setting the file_type parameter to xml, json, txt, or xls. Note that the default value of file_type is xml. The API key 'abcdefghijklmnopqrstuvwxyz123456' is for demonstration purposes only. Use a registered API key instead.

XML

Request (HTTP GET)

http://api.stlouisfed.org/fred/series/observations?series_id=GNPCA&api_key=abcdefghijklmnopqrstuvwxyz123456

Response

<observations realtime_start="2013-08-14" realtime_end="2013-08-14" observation_start="1776-07-04" observation_end="9999-12-31" units="lin" output_type="1" file_type="xml" order_by="observation_date" sort_order="asc" count="84" offset="0" limit="100000">
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1929-01-01" value="1065.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1930-01-01" value="975.5"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1931-01-01" value="912.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1932-01-01" value="794.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1933-01-01" value="783.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1934-01-01" value="866.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1935-01-01" value="944.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1936-01-01" value="1065.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1937-01-01" value="1120.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1938-01-01" value="1083.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1939-01-01" value="1170.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1940-01-01" value="1271.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1941-01-01" value="1497.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1942-01-01" value="1779.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1943-01-01" value="2081.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1944-01-01" value="2247.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1945-01-01" value="2224.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1946-01-01" value="1969.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1947-01-01" value="1950.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1948-01-01" value="2033.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1949-01-01" value="2021.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1950-01-01" value="2197.5"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1951-01-01" value="2376.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1952-01-01" value="2473.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1953-01-01" value="2587.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1954-01-01" value="2574.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1955-01-01" value="2758.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1956-01-01" value="2818.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1957-01-01" value="2878.5"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1958-01-01" value="2854.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1959-01-01" value="3050.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1960-01-01" value="3130.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1961-01-01" value="3211.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1962-01-01" value="3409.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1963-01-01" value="3559.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1964-01-01" value="3764.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1965-01-01" value="4008.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1966-01-01" value="4269.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1967-01-01" value="4386.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1968-01-01" value="4602.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1969-01-01" value="4745.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1970-01-01" value="4754.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1971-01-01" value="4913.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1972-01-01" value="5172.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1973-01-01" value="5475.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1974-01-01" value="5454.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1975-01-01" value="5430.4"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1976-01-01" value="5729.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1977-01-01" value="5997.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1978-01-01" value="6326.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1979-01-01" value="6547.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1980-01-01" value="6530.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1981-01-01" value="6688.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1982-01-01" value="6564.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1983-01-01" value="6863.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1984-01-01" value="7352.5"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1985-01-01" value="7640.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1986-01-01" value="7890.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1987-01-01" value="8161.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1988-01-01" value="8509.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1989-01-01" value="8822.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1990-01-01" value="9003.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1991-01-01" value="8988.6"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1992-01-01" value="9305.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1993-01-01" value="9559.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1994-01-01" value="9932.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1995-01-01" value="10206.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1996-01-01" value="10595.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1997-01-01" value="11058.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1998-01-01" value="11540.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="1999-01-01" value="12108.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2000-01-01" value="12614.3"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2001-01-01" value="12750.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2002-01-01" value="12970.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2003-01-01" value="13352.2"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2004-01-01" value="13879.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2005-01-01" value="14340.8"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2006-01-01" value="14690.9"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2007-01-01" value="15009.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2008-01-01" value="15009.0"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2009-01-01" value="14565.1"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2010-01-01" value="14966.5"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2011-01-01" value="15286.7"/>
<observation realtime_start="2013-08-14" realtime_end="2013-08-14" date="2012-01-01" value="15693.1"/>
</observations>

JSON

Request (HTTP GET)

http://api.stlouisfed.org/fred/series/observations?series_id=GNPCA&api_key=abcdefghijklmnopqrstuvwxyz123456&file_type=json

Response

{
    "realtime_start": "2013-08-14",
    "realtime_end": "2013-08-14",
    "observation_start": "1776-07-04",
    "observation_end": "9999-12-31",
    "units": "lin",
    "output_type": 1,
    "file_type": "json",
    "order_by": "observation_date",
    "sort_order": "asc",
    "count": 84,
    "offset": 0,
    "limit": 100000,
    "observations": [
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1929-01-01",
            "value": "1065.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1930-01-01",
            "value": "975.5"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1931-01-01",
            "value": "912.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1932-01-01",
            "value": "794.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1933-01-01",
            "value": "783.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1934-01-01",
            "value": "866.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1935-01-01",
            "value": "944.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1936-01-01",
            "value": "1065.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1937-01-01",
            "value": "1120.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1938-01-01",
            "value": "1083.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1939-01-01",
            "value": "1170.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1940-01-01",
            "value": "1271.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1941-01-01",
            "value": "1497.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1942-01-01",
            "value": "1779.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1943-01-01",
            "value": "2081.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1944-01-01",
            "value": "2247.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1945-01-01",
            "value": "2224.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1946-01-01",
            "value": "1969.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1947-01-01",
            "value": "1950.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1948-01-01",
            "value": "2033.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1949-01-01",
            "value": "2021.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1950-01-01",
            "value": "2197.5"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1951-01-01",
            "value": "2376.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1952-01-01",
            "value": "2473.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1953-01-01",
            "value": "2587.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1954-01-01",
            "value": "2574.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1955-01-01",
            "value": "2758.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1956-01-01",
            "value": "2818.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1957-01-01",
            "value": "2878.5"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1958-01-01",
            "value": "2854.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1959-01-01",
            "value": "3050.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1960-01-01",
            "value": "3130.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1961-01-01",
            "value": "3211.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1962-01-01",
            "value": "3409.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1963-01-01",
            "value": "3559.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1964-01-01",
            "value": "3764.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1965-01-01",
            "value": "4008.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1966-01-01",
            "value": "4269.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1967-01-01",
            "value": "4386.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1968-01-01",
            "value": "4602.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1969-01-01",
            "value": "4745.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1970-01-01",
            "value": "4754.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1971-01-01",
            "value": "4913.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1972-01-01",
            "value": "5172.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1973-01-01",
            "value": "5475.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1974-01-01",
            "value": "5454.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1975-01-01",
            "value": "5430.4"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1976-01-01",
            "value": "5729.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1977-01-01",
            "value": "5997.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1978-01-01",
            "value": "6326.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1979-01-01",
            "value": "6547.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1980-01-01",
            "value": "6530.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1981-01-01",
            "value": "6688.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1982-01-01",
            "value": "6564.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1983-01-01",
            "value": "6863.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1984-01-01",
            "value": "7352.5"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1985-01-01",
            "value": "7640.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1986-01-01",
            "value": "7890.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1987-01-01",
            "value": "8161.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1988-01-01",
            "value": "8509.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1989-01-01",
            "value": "8822.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1990-01-01",
            "value": "9003.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1991-01-01",
            "value": "8988.6"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1992-01-01",
            "value": "9305.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1993-01-01",
            "value": "9559.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1994-01-01",
            "value": "9932.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1995-01-01",
            "value": "10206.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1996-01-01",
            "value": "10595.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1997-01-01",
            "value": "11058.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1998-01-01",
            "value": "11540.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "1999-01-01",
            "value": "12108.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2000-01-01",
            "value": "12614.3"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2001-01-01",
            "value": "12750.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2002-01-01",
            "value": "12970.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2003-01-01",
            "value": "13352.2"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2004-01-01",
            "value": "13879.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2005-01-01",
            "value": "14340.8"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2006-01-01",
            "value": "14690.9"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2007-01-01",
            "value": "15009.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2008-01-01",
            "value": "15009.0"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2009-01-01",
            "value": "14565.1"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2010-01-01",
            "value": "14966.5"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2011-01-01",
            "value": "15286.7"
        },
        {
            "realtime_start": "2013-08-14",
            "realtime_end": "2013-08-14",
            "date": "2012-01-01",
            "value": "15693.1"
        }
    ]
}

Parameters

api_key

Read API Keys for more information.

file_type

A key or file extension that indicates the type of file to send.

series_id

The id for a series.

realtime_start

The start of the real-time period. For more information, see Real-Time Periods.

realtime_end

The end of the real-time period. For more information, see Real-Time Periods.

limit

The maximum number of results to return.

offset

sort_order

Sort results is ascending or descending observation_date order.

observation_start

The start of the observation period.

observation_end

The end of the observation period.

units

A key that indicates a data value transformation.

frequency

An optional parameter that indicates a lower frequency to aggregate values to. The FRED frequency aggregation feature converts higher frequency data series into lower frequency data series (e.g. converts a monthly data series into an annual data series). In FRED, the highest frequency data is daily, and the lowest frequency data is annual. There are 3 aggregation methods available- average, sum, and end of period. See the aggregation_method parameter.

aggregation_method

A key that indicates the aggregation method used for frequency aggregation. This parameter has no affect if the frequency parameter is not set.

output_type

An integer that indicates an output type.

vintage_dates

A comma separated string of YYYY-MM-DD formatted dates in history (e.g. 2000-01-01,2005-02-24). Vintage dates are used to download data as it existed on these specified dates in history. Vintage dates can be specified instead of a real-time period using realtime_start and realtime_end.

Sometimes it may be useful to enter a vintage date that is not a date when the data values were revised. For instance you may want to know the latest available revisions on 2001-09-11 (World Trade Center and Pentagon attacks) or as of a Federal Open Market Committee (FOMC) meeting date. Entering a vintage date is also useful to compare series on different releases with different release dates.