ocular pressure

I was wondering if those doing self-tonometry might be able to answer a question for me?  If I go with the general assumption that pressures are highest in the morning upon arising, how long does it usually take for the pressures to drop?  Is there an initial drop just minutes with a gradual tapering, or does it drop when a person stands and begins walking around?  I have tried to exercise immediately upon arising with the hopes of reducing the overall length of time that the pressure is high.  Thanks for the help.