An Amended Formula for the Decay of Radioactive Material for Cosmic Times

An amended formula for the decay of radioactive material is presented. It is a modification of the standard exponential formula. The new formula applies for long cosmic times that are comparable to the Hubble time. It reduces to the standard formula for short times. It is shown that the material decays faster than expected. The application of the new formula to direct measurements of the age of the Universe and its implications is briefly discussed.