improve text for 1st and last year level README

2020/index.html

@@ -55,7 +55,7 @@
 <div class="topnav">
   <a class="Left" href="../2019/index.html">&larr; 2019</a>
   <a class="Left" href="../index.html">&uarr; top &uarr;</a>
-  <a class="Left Disabled" href="#">In most recent year</a>
+  <a class="Left Disabled" href="#">No next</a>
   <a class="Right" href="#inventory">Inventory</a>
 </div>