Complex sentence: In April 2006, the ISPE had 583 members in 29 countries, although the majority (81.65%) resided in the USA in 45 states and the District of Columbia.
Split into simpler sentences: In April 2006, the ISPE had 583 members in 29 countries. The majority of members (81.65%) resided in the USA in 45 states and the District of Columbia.