I Am Curious About Calcium. I Just Looked At An

I am curious about calcium. I just looked at an NIH study the compared whole milk, chocolate milk, yogurt, cheese, and calcium carbonate for calcium utilization. As I recall there was no substantial difference with maybe around 25% absorb ability based on 250 mg. that would mean that about 62 mg would be absorbed. Maybe for post menopausal that would be310 would be absorbed based on 1250 total. Does that sound right? If you want to increase bone density should you take more calcium or add strontium at night?