When I try to find figures for the amount of helium today and just after the Big Bang, I get similar figures. I was expecting that all of the stars since then would have created more helium. Is the amount below our ability to estimate? Is helium being consumed at a similar or greater rate to produce heavier elements?
Alternatively, can we measure/ estimate a drop in the hydrogen? I presume that little hydrogen is being created. I am unaware of any common nuclear process which creates lone protons. (Please correct me if appropriate.)
Clarification: The Wikipedia Big Bang article mentions helium being created after a few minutes in the Big Bang nucleosynthesis. So, it is helium created after this point that I am asking about. I am presuming that negligible helium was created between this point and the first stars much later. (Again, please correct me if I am wrong.)