You need something like this
<br /><table border="1" cellspacing="0" style="font-family:Calibri,Arial; font-size:11pt; background-color:#ffffff; "> <colgroup><col style="font-weight:bold; width:30px; " /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:58.93px;" /><col style="width:143.52px;" /></colgroup><tr style="background-color:#cacaca; text-align:center; font-weight:bold; font-size:8pt; "><td > </td><td >A</td><td >B</td><td >C</td><td >D</td><td >E</td><td >F</td><td >G</td><td >H</td><td >I</td><td >J</td><td >K</td><td >L</td><td >M</td></tr><tr style="height:37px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >12</td><td style="background-color:#92d050; ">Q1 2011</td><td style="background-color:#92d050; ">Q2 2011</td><td style="background-color:#92d050; ">Q3 2011</td><td style="background-color:#92d050; ">Q4 2011</td><td style="background-color:#92d050; ">Q1 2012</td><td style="background-color:#92d050; ">Q2 2012</td><td style="background-color:#92d050; ">Q3 2012</td><td style="background-color:#92d050; ">Q4 2012</td><td style="background-color:#92d050; ">Q1 2013</td><td style="background-color:#92d050; ">Q2 2013</td><td style="background-color:#92d050; ">Q3 2013</td><td style="background-color:#92d050; ">Q4 2013</td><td style="background-color:#92d050; ">Average of highest 4 consecutive months</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >13</td><td style="text-align:right; ">34,150</td><td style="text-align:right; ">41,888</td><td style="text-align:right; ">42,699</td><td style="text-align:right; ">39,514</td><td style="text-align:right; ">55,818</td><td style="text-align:right; ">41,968</td><td style="text-align:right; ">13,140</td><td style="text-align:right; ">17,211</td><td style="text-align:right; ">17,910</td><td style="text-align:right; ">32,589</td><td style="text-align:right; ">13,917</td><td style="text-align:right; ">27,598</td><td style="text-align:right; ">44,999.75</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >14</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td >sum each 4 months</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >15</td><td style="text-align:right; ">34,150</td><td style="text-align:right; ">41,888</td><td style="text-align:right; ">42,699</td><td style="text-align:right; ">39,514</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">158,251</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >16</td><td > </td><td style="text-align:right; ">41,888</td><td style="text-align:right; ">42,699</td><td style="text-align:right; ">39,514</td><td style="text-align:right; ">55,818</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">179,919</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >17</td><td > </td><td > </td><td style="text-align:right; ">42,699</td><td style="text-align:right; ">39,514</td><td style="text-align:right; ">55,818</td><td style="text-align:right; ">41,968</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="background-color:#ffff00; text-align:right; ">179,999</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >18</td><td > </td><td > </td><td > </td><td style="text-align:right; ">39,514</td><td style="text-align:right; ">55,818</td><td style="text-align:right; ">41,968</td><td style="text-align:right; ">13,140</td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">150,440</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >19</td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">55,818</td><td style="text-align:right; ">41,968</td><td style="text-align:right; ">13,140</td><td style="text-align:right; ">17,211</td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">128,137</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >20</td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">41,968</td><td style="text-align:right; ">13,140</td><td style="text-align:right; ">17,211</td><td style="text-align:right; ">17,910</td><td > </td><td > </td><td > </td><td style="text-align:right; ">90,229</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >21</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">13,140</td><td style="text-align:right; ">17,211</td><td style="text-align:right; ">17,910</td><td style="text-align:right; ">32,589</td><td > </td><td > </td><td style="text-align:right; ">80,850</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >22</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">17,211</td><td style="text-align:right; ">17,910</td><td style="text-align:right; ">32,589</td><td style="text-align:right; ">13,917</td><td > </td><td style="text-align:right; ">81,627</td></tr><tr style="height:19px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >23</td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td > </td><td style="text-align:right; ">17,910</td><td style="text-align:right; ">32,589</td><td style="text-align:right; ">13,917</td><td style="text-align:right; ">27,598</td><td style="text-align:right; ">92,014</td></tr></table>
Add every 4 columns, but I do not know how it would be with a formula.
I give you an example macro to get the result of row 13
Code:
Sub highest_4()
wMax = 0
For i = Columns("A").Column To Columns("L").Column - 3 'Step 4
wSuma = WorksheetFunction.Sum(Range(Cells(13, i), Cells(13, i + 3)))
If wSuma > wMax Then wMax = wSuma
Next
Range("M13").Value = wMax / 4
End Sub
Maybe someone will review it and help you with the formula, while you can use the macro option.