Is NYC's congestion pricing working to improve traffic in Manhattan? Here's a look at the MTA data for the first three weeks.

Drive times into Manhattan have dropped dramatically since the institution of New York’s congestion tolling program, according to data released Wednesday by the MTA — with the most significant improvements at the Holland Tunnel.

New York's congestion pricing has led to 1 million total fewer vehicles entering the busiest part of Manhattan and cut commuting times since the program began on Jan. 5, a transit agency said on Wednesday.

The analysis did not include changes to travel speeds on the George Washington Bridge or Cross-Bronx Expressway. The environmental assessment published by the MTA before the tolls launch expected traffic in those areas to increase slightly as drivers tried to circumvent the congestion pricing fees.

CNBC's Mike Santoli reports on the latest news.