It is common place for official statistics to be massaged by the authorities.
In the UK, for example they have waiting lists of people who are booked in to get an operation. However, government regulations stipulate that all hospitals must not make patients more than a certain amount of time before getting their operation. In order to achieve the government targets, it is not possible to get on a waiting list if it means that you would have to wait beyond the statutory time allowed.
Honestly, this actually is a common problem in the world. The U.S. bureau that calculates GDP uses understated inflation figures. If you use inflation figures from two other government groups we would actually already be in a technical recession and those inflation figures are also believed to be understated. So if our government was being honest the U.S. would already be officially in a recession.
However, if the U.S. was declared to be in a recession you'd have the stock market plummeting and it would reverberate in other countries like Japan, the UK, and Germany.
This is how government typically operates. It wants to maintain good feelings and is willing to lie or exaggerate to do so. China just has this problem even worse. That's because even if China was still growing faster than any other country any drop in GDP by more than two points would be seen as a disaster. Asia would be pummeled and the U.S. would suffer considerably, especially right now.
It's not a slight against any individual though, it's easy to understand why governments do it even if it does no one any benefit. However, delusions are more dangerous than truth most of the time.