Is that meant to be a pie chart showing percentage? The picture is small and I can't zoom in. It looks like it's just showing what's in the mix. So it doesn't list an actual percentage for the calcium like it does the protein? My guess would be it's probably about 1-2% then so you don't have to worry about kidney damage. 
You'll know if it's not enough if you get any soft-shelled eggs. Or you could do a little experiment and give her some dry, crushed up shells on the side. If she eats them it means she needed calcium but if she leaves them she's getting enough. That's what I have to do with mine because my feed doesn't have enough for the females. I have a mixed flock and the males don't need high amounts so it's easier for me just to give it on the side and let the girls take what they need. I think it's cool how they 'know' exactly how much they need.
You'll know if it's not enough if you get any soft-shelled eggs. Or you could do a little experiment and give her some dry, crushed up shells on the side. If she eats them it means she needed calcium but if she leaves them she's getting enough. That's what I have to do with mine because my feed doesn't have enough for the females. I have a mixed flock and the males don't need high amounts so it's easier for me just to give it on the side and let the girls take what they need. I think it's cool how they 'know' exactly how much they need.
