OVERVIEW
AVAILABILITY
SOURCES
DEFINITIONS
BREAKS AND VALUATIONS
FURTHER INFORMATION
OVERVIEW
Notes and coin is the narrowest measure of money published. Reserve balances are interest-bearing balances held by banks and building societies at the Bank of England. Until the Bank's Money Market Reforms in May 2006 another narrow measure of money, M0, was also published. For information about the old M0 series, see here.

AVAILABILITY
Weekly data are collected every Wednesday. Monthly data are computed as the average of the four or five weekly figures for the month.
Weekly data are available from 1990 for notes and coin and from May 2006 for reserve balances. Monthly data are available from 1969 for notes and coin and from May 2006 for reserve balances. Notes and coin and reserve balances data are available in Table A1.1.1 of Monetary and Financial Statistics. The monthly notes and coin data is available both not seasonally adjusted and seasonally adjusted, and there is also an additional series which is adjusted for special non-seasonal factors, such as the £1 note write-off in 1998, the funding of the winter fuel payments, the turn of the millennium, the fuel dispute of 2000, and the threatened strike action affecting note distributors in 2003. Reserve balance data are not seasonally adjusted in this presentation.
The average outturns for the month are published in the Narrow money (notes and coin) and reserve balances release, on the first Wednesday of the following month. Individual weekly observations are updated on the Bank's Statistical Interactive Database at the same time.

SOURCES
The level of notes in circulation and information about reserve balances are taken from the Bank of England's balance sheet. Coin data are provided by the Royal Mint, and information about the net issues of the Scottish and Northern Irish note-issuing banks adjusted for set-aside Bank of England notes) is provided by the banks themselves.
All data are subject to revision if and when new information becomes available. For more information on revisions practices see the Explanatory Note on revisions, available here.

DEFINITIONS
Notes and coin comprises sterling notes and coin in circulation outside the Bank of England (including those held in banks' and building societies' tills). Notes and coin, as presented in the monthly statistical release, differs from the series within M4 and other balance sheet statistics because it is compiled as an average of weekly observations (as opposed to an end-month position) and because it includes all holdings of notes and coin, not only those held by the non-bank, non-building society private sector.
From November 2009 notes and coin in circulation represents all holdings outside the Bank of England (including those in banks' and building societies' tills), but excluding backing assets for commercial banknote issue in Scotland and Northern Ireland. For details, see the October 2009 article in Monetary & Financial Statistics at: www.bankofengland.co.uk/statistics/ms/articles/art1oct09.pdf.
Following the implementation of Money Market Reform by the Bank of England on 18th May 2006, banks and building societies that are required to hold cash ratio deposits at the Bank were entitled to place further deposits (reserve balances) earning interest at the Bank's Rate. These deposits are voluntary and subject to a target level, chosen by the account holder, which they must meet, on average, over a maintenance period lasting from one scheduled MPC announcement date to another. Amounts held as reserve balances can be used in the same way as former bankers' operational deposits, meaning the latter are no longer identifiable.

BREAKS AND VALUATIONS
Following Bank of England Money Market Reform on 18 May 2006, Table A1.1.1 in Monetary and Financial Statistics replaced Table A1.1. Many of the series in Table A1.1 are continued in Table A1.1.1, though for M0 and bankers' operational deposits data the final observations are for April 2006, and the first observation for reserve balances data is for May 2006. More information on changes made to the Bank's monetary policy operations and their impact on published data can be found in 'The implications of money market reform for data published in Monetary and Financial Statistics' in the June 2006 issue of Monetary and Financial Statistics.

FURTHER INFORMATION
- Janssen, N and Andrews, P (2005), 'Publication of narrow money data: the implications of money market reform', Bank of England Quarterly Bulletin, Autumn 2005.
- Bank of England (2006) 'The implications of money market reform for data published in Monetary and Financial Statistics', Monetary and Financial Statistics, June 2006.
- Bank of England (2007), 'Proposed changes to broad and narrow money statistical releases: consultation with users', Monetary and Financial Statistics, August 2007.