1. Gold Valuation
Gold in millions of US$ in the RT database is reported by the authorities and market valuation is recommended. Gold in millions of US$ in IFS is calculated by converting the gold volume in millions of fine troy ounces reported by the authorities into SDRs at SDR 35 per ounce, and then applying the US$/SDR end of period exchange rate. This accounts for most of the difference between the RT and IFS.
2. Fund Accounts
There is a slight difference in SDR holdings because the SDR holdings in the RT are reported according to the countries' records. SDR holdings in IFS are the official figures from the IMF's Finance Department (FIN).
3. Foreign Exchange
Foreign exchange in the IFS consists of a single reported value. In the RT, foreign exchange is the sum of Foreign Currency Reserves (in convertible foreign currencies) plus Other Reserve Assets. Technically, foreign exchange in IFS and foreign exchange as derived from RT components should be the same.
The IFS dataset can be found here.
The RT dataset can be found here.