Complex sentence: Since the introduction of the E- 3 visas, between 2,000-3,000 E- 3 visas have been issued by US consulates to Australian professionals every year; in addition to this, E3R visas are issued to the returning Australian professionals whose original visas had expired.
Split into simpler sentences: Since the introduction of the E- 3 visas, between 2,000-3,000 E- 3 visas have been issued by US consulates to Australian professionals every year. In addition to this, E3R visas are issued to the returning Australian professionals whose original visas had expired.