When did MicroStrategy start buying bitcoin?

Could you elaborate on the timeline of MicroStrategy's decision to enter the cryptocurrency market, specifically with regard to its initial purchases of bitcoin? What year or quarter did this investment strategy commence? Were there any preceding events or factors that led to this shift in financial strategy? And furthermore, what has been the impact of these bitcoin purchases on MicroStrategy's overall financial performance and market position? Understanding the context and motivation behind this move is crucial for assessing its long-term significance and implications for both MicroStrategy and the cryptocurrency market at large.