Microsoft Corp.'s /zigman2/quotes/207732364/composite MSFT -0.23% collaborative-communications platform, Teams, continues to post huge gains in the wake of the coronavirus pandemic. The company on Thursday said a record of 2.7 billion meeting minutes were logged on March 31, an increase of 200% from 900 million in mid-March. Total video calls grew 1,000% in March. And the Pentagon recently launched a Microsoft-based teleworking service for 4 million employees. Microsoft, which is locked in competition with Slack Technologies Inc. /zigman2/quotes/212180539/composite WORK +6.08% , last month said Teams reached 44 million people on a daily basis - up from 32 million on March 11 and 20 million in November. Microsoft shares are up 4.5% in the last year. The broader S&P 500 index /zigman2/quotes/210599714/realtime SPX +0.38% is down 3% in the last year.