Complex sentence: It is estimated that its work has led to nearly 3000 prosecutions since 2009, though that number is increasing from 300 in 2009 to over 1000 in 2013.
Split into simpler sentences: It is estimated that its work has led to nearly 3000 prosecutions since 2009. The number of prosecutions each year has risen from 300 in 2009 to over 1000 in 2013.