When you are suffering from stage 2 COPD, the limitations of air flow becomes worse, and symptoms may become noticeable. More importantly, you will begin to experience cough, shortness of breath and increased production of sputum. The FEVI drops to between 50% and 79% of the normal value while the FEVI/FVC becomes less than 70%. In stage 2 COPD, most people can notice some problem and seek medical treatment.