The decay of carbon-14
which has a half-life of 5730 years
time in years % left Scroll down to view the decay curve
0 100.00
5730 50.00
11460 25.00    
17190 12.50    
22920 6.25
28650 3.13
34380 1.56 The data are 'perfect' to illustrate
40110 0.78 the halving of the remaing isotope
45840 0.39 after the time lapse of a half-life
half-life = 5730 years    
   
after every 5730 years    
   
the % of the isotope    
   
carbon-14 left is    
   
is half what it was