Percentage of available images in pixmo

Hi,

I'm wondering if there's an estimate of the percentage of images still available from the released urls? For instance, when I'm downloading images from the `allenai/pixmo-cap` dataset with the provided `scripts/download_data.py`, I'm only getting `555451/716551 (77.52%)` of all the images in `allenai/pixmo-cap`.

I'm wondering if there's some issue with my data downloading or if this is about the right amount of data that's still available.

Thanks very much!