Well I had a look and as it turns out CEX.IO just charge A LOT for their BTC - about $200 more (which explains this chart).
There are more affordable ways to get your coins so have a look at the other exchanges listed in the chart.
Aviso legal
As informações e publicações não devem ser e não constituem conselhos ou recomendações financeiras, de investimento, de negociação ou de qualquer outro tipo, fornecidas ou endossadas pela TradingView. Leia mais em Termos de uso.
There are more affordable ways to get your coins so have a look at the other exchanges listed in the chart.