The world's leading cryptocurrency, bitcoin (BTC-USD +1.6%) holds its ground over $42K, but it's still off by 10% in September — the biggest decline since May — and the same month where the stock market (SP500) also started to get a bit choppy, according to CoinDesk 20 data. Much of the selling in BTC this month came from new investors as "older market participants are sitting tight on their holdings, shown by the average lifespan of spent outputs declines," according to Blockware Intelligence's newsletter from Sept. 17. China's ban on crypto transactions and mining, as well as the Federal Reserve's asset tapering set to begin as soon as next quarter, shouldn't be much of a bother to the price of BTC. Historically, BTC generates the biggest quarterly gains in the October to December period, analysts told CoinDesk. Still, a selloff in stocks could weigh on the token as "bitcoin's 90-day correlation