He's not trying to measure something in Poser. He's doing a render where he needs an oversize height chart. Mugshot of Godzilla? Growth chart for the young Jolly Green Giant?

I fear Bagginsbill is correct. Over 10', you have to make your own. Start with the 10' chart at ShareCG, then use Photoshop or something to edit the numbers to read what you want. Stack them, if you need to show the whole body instead of just a mug shot.