It was in the year 2013, when CoinmarketCap was launched. Back then they only tracked 7 cryptocurrencies, and a handful of exchanges and markets with a total market capitalisation of approximately 1.6 Billion USD.
As of May 1st, 2018, they are tracking over 1600 cryptocurrencies and 200 exchanges with a total market capitalization over $400 billion USD!
For more information visit
https://medium.com/@CoinMarketCap/coinmarketcaps-5-year-anniversary-587971c901f8