The British Museum has seen its annual fundraising income fall from £54.2m in 2014 to £23.3m in the most recent year, according to its annual report and accounts.
The museum is one of several exempt charities which is regulated directly by the Department for Culture, Media and Sport, although it has a friends group with an income of £5.1m which is registered with the Charity Commission.
The museum's most recent accounts, for the period to March 2018, were filed last week.
Fundraised income at the museum peaked at £54.2m in 2014 but has fallen every year since.
The museum did not give any explanation as to why fundraising income had fallen, although total income has also dipped – from £117.7m to £104.4m in the most recent year.
Expenditure on raising donations and legacies was £1.47m, compared to £1.42m the previous year.
The museum’s largest source of income was its government grant-in-aid, which was £53.6m, which remained and is almost the same as the previous year.