Unfortunately it is more complicated than a few data points. The rules for FHB grants have been changed by state and federal governments several times which qualifies the stats.
If you recall - i have asked from Rembrandt: a) % of FHB who buy for cash (don't register for a loan), b) % of FHB who enter the market as investors (not register for FHB grant), c) % of FHB who are not eligible for any government grants (i.e. not buying homes which are excluded from grants).
The ABS collects First Home Buyer data from the Survey of Income and Housing, which is conducted every few years going back to 1981, and from the monthly Housing Finance data (i.e. mortgage commitments). The only way that the ABS can identify First Home Buyers on a monthly basis is if a box is ticked on a form to say that the applicant is a FHB when applying for a loan.
There is an incentive to tick this box, but only if without the tick the applicant would not receive their First Home Buyer Grant or Stamp Duty exemption. However, the FHB Grants and Stamp Duty exemptions were recently cancelled in some States for purchases of existing property, so there is no longer an incentive to tick the box in the case of many FHB purchases.
First Home Buyers are active in the New Build and Off-The-Plan market (to which FHB grants do still apply in NSW, QLD and VIC). They obviously tick the FHB box when applying for finance, however, finance is not applied for until the new build is complete, which can be several years from the time of purchase (when only a deposit is paid). Therefore, any off-the-plan purchases made by FHBs today are not going to appear in the ABS housing finance data for a number of years.
You need to consider a range of factors & facts within context (as the Senate inquiry did in 2004) to understand FHB behavior.
If you are interested - you could do more research, but 'household formation' data is perhaps one of the most important 'predictor' of FHB property market.
