To fill all the blank cells with the value above the blank cell can be finished in two parts:
Part I: To select all the blank cells
Step 1: Click anywhere in the worksheet;
Step 2: Click the "Home" tab from the ribbon;
Step 3: Click Find&Select" and select "Go To Special" from the list;
Step 4: Check "Blanks" in the "Go To Special" window;
Step 4: Click "OK" at the bottom.
Part II: To fill blank cells with values
Step 5: After selecting all blank cells (please do not click your mouse):
1. Type "=" (equal sign) on your keyboard, this should be in your first blank cell;
2. Click your mouse on the cell above the first blank cell;
Step 6: Hold the "Ctrl" key, press "Enter" key from the keyboard. All blank cells should have the same value as the cells above.
Please note: the cell value is by formula at this point, you can use copy and paste special with value only to change formulas into values.