Right exchange rate for currency conversion for foreign income reporting?

Hi I have some foreign income in Indian Rupee for 2016 and hence need to convert to USD. I went through other similar questions regarding currency conversion rate and in few of those answers it was suggested to use the IRS provided rate (https://www.irs.gov/individuals/international-taxpayers/yearly-average-currency-exchange-rates), while in other answers it was advised to use Treasure Department exchange-rates (https://www.irs.gov/individuals/international-taxpayers/foreign-currency-and-currency-exchange-rates... (https://www.fiscal.treasury.gov/fsreports/rpt/treasRptRateExch/currentRates.htm). Now if I follow the first IRS link, the exchange rate is provided as 69.56, whereas Treasury Reporting Rates of Exchange as of December 31, 2016 for India is 67.8. Which rate am I suppose to use?