CPI-weighted USD/RUB exchange rate calculation
Projected target for USDRUB calculated by inflation rates (consumer price indexes) is 110.
//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)