It must be pointed out that the exchange rate dynamics in India for more than a decade has been driven by capital flows rather than current account balances. As an aside, India has mostly run a current account deficit, notwithstanding a bilateral trade surplus with the US, marginally more than USD 20 billion during 2018.
Though long-term flows related to FDI and long-term debt have been fairly stable keeping in tandem with the economic fundamentals, the portfolio flows have their own dynamics depending as much on 2/3  BIS central bankers' speeches  attractiveness of returns of Indian assets as the global factors determining their risk appetite.