Source: Federal Reserve Bank of St. Louis  

Release: Money Zero Maturity (MZM)  

Units:  Billions of Dollars, Not Seasonally Adjusted

Frequency:  Monthly

Notes:

This series has been discontinued and will no longer be updated. The institutional money market funds component (IMFNS) used to calculate this series has been discontinued by the Board of Governors and is no longer available in the H.6 statistical release, Money Stock Measures.

For further information about the changes to the H.6 statistical release, please see the announcements provided by the source.

M2 less small-denomination time deposits plus institutional money market funds.
Money Zero Maturity is calculated by the Federal Reserve Bank of St. Louis.

Source: Federal Reserve Bank of St. Louis  

Release: St. Louis Monthly Reserves and Monetary Base  

Units:  Billions of Dollars, Seasonally Adjusted

Frequency:  Monthly

Notes:

Updates of this series will be ceased on December 20, 2019. There is no replacement to this seasonally adjusted series. Interested users can construct a proxy of not seasonally adjusted data as the difference between monetary base from the H.3 release and currency component of M1 from the H.6 release. The discontinued series plotted on the same graph with the calculated data can be accessed for comparison here.
For more details, see the FRED Announcement.

Source: Board of Governors of the Federal Reserve System (US)  

Release: H.4.1 Factors Affecting Reserve Balances (data not included in press release)

Units:  Billions of Dollars, Not Seasonally Adjusted

Frequency:  Monthly

Notes:

Data prior to 1991 are from various issues of Banking and Monetary Statistics and the Annual Statistical Digest. Data from 1991 forward are calculated using data from the H.4.1 Release - Factors Affecting Reserve Balances.
As of March 1, 2019, this series is calculated as a monthly average of fred.stlouisfed.org/series/WCURCIR.