Flight level

[Crosswhinge]

I recently flew from Australia to Frankfurt on a ME carrier. For the first sector and half the second it was consistently mid way between FLs. Then for the second half it was flying very close to the FL within about 50ft as I usually see on flight tracking display. Why is this?

[Intruder]

Display probably used GPS altitude instead of ADC altitude.

[flyboyike]

Why is this?

Unfavorable exchange rate.