Both the American Lung Association and the San Joaquin Valley Air Pollution Control District have released their annual reports, showing that air quality in the Valley continues to improve despite the growing population and increase of cars. The report focuses on two main pollutants: Ozone and Particulate Matter, which can cause asthma, COPD, flu, pneumonia, heart disease, hypertension, and rheumatic fever. However, the report acknowledges that there is still a long way to go before 'healthy' air quality is considered. The Ozone problem is particularly acute in Visalia, with the 2nd and 5th worst rate out of over 200 US cities. Particulates Matter (PM) is also a significant issue in the area, with Bakersfield being the most polluted city in the nation with respect to Particulated Matter. China's contribution to air quality has dropped from 25% to 15%. The main contributors to our bad air quality are local weather patterns and local environmental conditions.