Where's the baby boom?

Germany's family minister liked to brag that due to increased financial incentives, Germans are at last having more kids. Unfortunately, 2008 birth statistics have just been released, and they show a decrease in 2008 births compared to 2007:

2006: 673,000
2007: 685,000 (+1.8%)
2008: 675,000 (-1.5%)

Based on these numbers, the press spins a story of policy failure. However, things aren't as bleak as they may appear at first glance:

The thing is that due to demographic changes, the number of women in prime childbearing age (in Germany, that tends to be the age bracket 30-40) is going down quite rapidly:

Total number of women aged 30-40:

2006: 5,486
2007: 5,279 (-3.8 %)
2008: 5,096 (-3.5 %)

(Data source: Destatis)

In other words, while births have decreased a bit in 2008, the number of births per woman aged 30-40 has actually gone up quite significantly in 2007, and was up again (albeit only slightly) in 2008.

This can also be seen in the fertility rate, which went from 1.33 in 2006 to 1.37 in 2007. 2008 numbers haven't yet been calculated, but it's likely that it has increased a bit further, probably to 1.38.

Sure, it's not exactly a baby-boom, and compared to countries like France, Britain and the US, the fertility rate is still extremely low. But at least things aren't getting worse, they appear to be getting just a tiny little bit better.

(In any case, statisticians will probably argue that changes of such small magnitude are not statistically significant, so we might as well assume the underlying long-term fertility rate is simply constant...)