The Peter's Pence collection is the donations from dioceses and Catholic Christians around the world to the Pope of Rome. The Vatican has since 2013 failed to explain how much it collects and how these alms are spent.
'You must know that the donations that his faithful donate to him each year through the St. Peter's Pence are not spent on the poorest, but accumulate in accounts and investments. [...] In practice, the money of the Pence, when it is not kept under the mattress or invested in financial markets, is used for the economic needs of the dicasteries and of the Roman cardinals, and not in works of charity.'
Fittipaldi, Emiliano. Avarice. Francesco Giangiacomo Feltrinelli Editore Milano, 2015.