Bitcoin (BTC) just ended what is historically the largest cryptocurrency's third-worst week of the year with a greater-than-average drop of 5%. Week 38 effectively closes out the third quarter, which is up about 1%, as well as September, which has managed to hold flat. While the figures are consistent with the period's historical reputation as one of the weakest seasons of the year, a few catalysts might have contributed to the underperformance. On Friday, more than $17 billion in options expired, with t ...