According to a report released on Thursday by California Air Pollution Control Officers Association (CAPCOA), the state's air quality is in much better shape than it was in 1990.

The CAPCOA report is compiled from information provided by the administrators of 35 air quality management districts in California. The reported released on Thursday was the second major report this year that pointed to better air quality in the region.

The issued report showed that compared to levels in 2014, toxic emissions from all sources have dropped 80%. Smog-forming emissions declined by 50% since 1990.

Compared with the data 12 years ago, those residents in Orange, Riverside and San Bernardino counties now get roughly triple the number of good-air days. The lung strength of children living in Riverside, Jurupa Valley, Upland, San Dimas and Long Beach has improved significantly as air pollution dropped in the past 20 years.

California's gross economic production has nearly doubled since 1990 while smog-forming emissions were cut in half. The main reason behind success in reducing pollution is the state's tougher limits on tailpipe emissions for cars and trucks and efforts by regional air districts to cut pollution from factories, power plants and other nonmoving sources.

However, he said that the state still has more work to do and more improvements are expected.