The numbers for China are ridiculously out of date. Eg. The Q-5 was officially retired several years ago, yet the paper claims there are over 100 in service. The amounts estimated for new types (J-20, Y-20) are roughly the same as what there is photo evidence for, which I guess is understandable. But the biggest offense is the gross underestimation in the airframe types which have been mass produced in the past 10-15 years, such as J-10, -11, -16, H-6 and JH-7.
Overall I would consider the tally in the annual IISS Military Balance publication to be more accurate. They seem to use estimates based on factors such as presumed production rates, the number of units operating each type, and some informed guesswork. And when it comes to following the Chinese military, that's a lot better than waiting for photo confirmation of each individual airframe when there are hundreds.
But World's Airforces is a good publication for following militaries that are more open. I was definately delighted to see it published yesterday.
