In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.
//CPI_RUS = PRICE_RUS_PRODUCTS / PRICE_RUB //CPI_USA = PRICE_US_PRODUCTS / PRICE_USD //PRICE_RUS_PRODUCTS != PRICE_US_PRODUCTS //PRICE_USD / PRICE_RUB [year 1999] = 22 //PRICE_RUS_PRODUCTS / PRICE_US_PRODUCTS [year 1999 and => now] = CPI_RUS / CPI_USA / 22 = 0.02 //PRICE_USD / PRICE_RUB [now] = CPI_RUS / CPI_USA / 0.02 = 50 * CPI_RUS / CPI_USA study("CPI-weighted USD/RUB exchange rate calculation", overlay=true) s = 50 * security("QUANDL:RATEINF/CPI_RUS","M",close) / security("QUANDL:RATEINF/CPI_USA","M",close) plot(s, linewidth=2)