As I explained last year Jeffro, it’s simply impossible to inflate the “growth rate” for long periods of time without the two measure drifting apart from one another. If the growth rate was consistently overstated for many years you would end up with JWs claiming a lot more members than other measures produce. This has not happened, ever.
Or look at it another way, and ignore Watchtower figures altogether and what do we find? As with the latest New Zealand data, they show that JWs are growing while almost all other Christian groups are declining. The only other Christian group with any significant growth in New Zealand is the Seventh-day Adventists. The Baptists are remaining about level, and most other groups are declining heavily. These data are derived without looking at Watchtower’s own figures at all.
Plus there are aspects of the Watchtower report that are likely to be highly accurate, such as number of congregations, which can be independently verified, and the number of baptisms, which is likely to be accurately recorded, and is not subject to change in definition of what “baptism” means.
Your only argument boils down to the claim that the definition of “publisher” this year may be a bit more liberal than the definition of “publisher” last year, and granted in some individual years this is probably the case, such as when the 15 minute rule was introduced in the early 2000s. Over the long term, however, the number of members that JWs claim remains much lower than the number of self identified JWs in national censuses, and often by significant amounts. Some countries, especially in South America, have close to double the number self identified JWs compared with the Watchtower “publisher” count. This is in stark contrast with Mormons who often claim twice, three times, even four times as many members in their official count compared with census results.