Nearly all of my better quality H264 HD movies have peak video bitrates of anywhere between 20 and 60Mbits/s and, for reference, the official total peak AV bitrate for BD Video movies is 48Mbits/s.
Simply going by file size versus duration to calculate bitrate won't work as that only gives you the average bitrate, not the peak. The peak bitrate can often reach 6x the average in CQ-mode, and any decent encoding will almost definitely have been made in CQ-mode.
I suppose the real question is whether the OP means 24Mbits/s or 24MB/s. If it's the latter, then all of the above is irrelevant in this case.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.