Recently someone at Davos asked a PRC rep about this and he mentioned the number is close but is often different due to smoothening.
He did mention it is close and showed that tax revenues grew quite close to the GDP rate. This is something that does not typically happen when GDP decreases or is far off from the actual numbers.
There are many economic indicators that correlate to GDP growth, but are also influenced by other factors and so the strength of the correlation can be strong or weak at any given time. This means at any given moment you can probably pick or chose one or more other indicators to back up any particular contention about GDP, but that doesn't really prove anything. To get a good picture you need to look at a wide variety of indicators. If the vast majority of them indicate the GDP growth measure is wrong, then even if a few of them back it up it's still likely that the growth measure is being fiddled.
There are many but wouldn't you agree tax revenues are a rather hard indicator to fudge if GDP decreases? Tax revenues are very well correlated to GDP, in downturns too.
6% is also a rather large increase YoY for the Chinese MoF's tax receipts. It is difficult to make hard cash of such a large number up.
I think what has happened is China actually grew faster than the claimed 7-9% in the past decade and now the amount is smoothened to reflect this
I've always noticed a sway on HN to downplay China's growth, given the large American audience this is quite expected. But it is good to be impartial to understand the changes a bit better.
There are many related indicators that you can't easily "fudge".
Actors who have a stake in China's growth (or lack thereof) aren't simply looking at a PDF posted by the Chinese government.
For example, China is now Brazil's largest trading partner. In particular, it's the biggest importer of Brazilian goods (e.g. oil and iron). When China's manufacturing output grows or drops, its demand for Brazilian exports grows or drops too.
(One could probably make a stronger case by looking at e.g. Gulf countries instead of Brazil)
