title: Adding value to the last cell
body: <p>I need help with something, in theory at least, simple:</p>
  
  <p>You enter any value in one cell (A1), that value is added to B1. You add another value (replacing the previous value) in A1, C1 is created with that value, and goes on.</p>
  
  <p>I need to keep that history saved, but at the same time, simplifying the input method.</p>
  
  <p>I would really appreciate any help. Thanks.</p>