How to set transition alt on appr 737

I can set the transition for departure, and it shows on the vnav page for climb. However on approach it defaults back to 7000 in Europe. Appr ref page 2 is blank so maybe it's there on the real fmc?

OK I will have another look later thanks.

Quote from Jet-Pack (IPACS)

If I remember correctly it's on VNAV descent prediction...

Thanks I have found it now, on the DES Forecasts page.