Se puede crear una fórmula PROMEDIO.SI usando una fórmula matricial. El siguiente ejemplo muestra lo que digo: (Las fórmulas quedan en Inglés).
IF = SI
LEN = LARGO
AVERAGE = PROMEDIO
Para ingresar una fórmula matricial hay que hacerlo con Control Shift Enter, en vez de solo Enter.
<CENTER><TABLE ALIGN=CENTER BORDER=1 BORDERCOLOR=#C0C0C0 CELLSPACING=0><TR><TD COLSPAN=5 BGCOLOR=#0C266B ><TABLE ALIGN=CENTER BORDER=0 WIDTH=100%><TR><TD ALIGN=LEFT><FONT COLOR=WHITE>Microsoft Excel - Libro1</FONT></TD><TD ALIGN=RIGHT><FONT COLOR=WHITE SIZE=2>___Running: xl2000 : OS = Windows (32-bit) 4.90</FONT></TD></TR></TABLE></TD></TR><TR><TD BGCOLOR=#D4D0C8 COLSPAN=5>(<U>F</U>)ile (<U>E</U>)dit (<U>V</U>)iew (<U>I</U>)nsert (<U>O</U>)ptions (<U>T</U>)ools (<U>D</U>)ata (<U>W</U>)indow (<U>H</U>)elp</TD></TR><TR><TD BGCOLOR=WHITE COLSPAN=5><TABLE BORDER=0><TR><TD COLSPAN=5% ALIGN=CENTER BGCOLOR=White>A1</TD><TD COLSPAN=10% ALIGN=RIGHT BGCOLOR=#D4D0C8 >=</TD><TD COLSPAN=85% ALIGN=LEFT BGCOLOR=White>CLIENTE</TD></TR></TABLE></TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER>
</TD><TD BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>A</CENTER></TD><TD BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>B</CENTER></TD><TD BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>C</CENTER></TD><TD BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>D</CENTER></TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>1</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>CLIENTE</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>CALI1</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>CALI2</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>2</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>A</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>4</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>4</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>3</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>B</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>4</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>3</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>4</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>A</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>1</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>5</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>B</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>2</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>2</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>6</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>B</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>1</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>7</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>A</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>1</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>8</CENTER></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>9</CENTER></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>10</CENTER></TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>11</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>CLIENTE</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>CALI1</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000000>CALI2</FONT></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>12</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>A</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><A HREF=javascript:alert('{=AVERAGE(IF(($A$2:$A$7=$A12)*LEN(B$2:B$7),B$2:B$7))}')><FONT FACE=Arial COLOR=#000000>2.000</FONT></A></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><A HREF=javascript:alert('{=AVERAGE(IF(($A$2:$A$7=$A12)*LEN(C$2:C$7),C$2:C$7))}')><FONT FACE=Arial COLOR=#000000>4.000</FONT></A></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD WIDTH=1% BGCOLOR=#D4D0C8 ALIGN=CENTER><CENTER>13</CENTER></TD><TD BGCOLOR=#FFFFFF ALIGN=Left VALIGN=BOTTOM ><FONT FACE=Arial COLOR=#000080>B</FONT></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><A HREF=javascript:alert('{=AVERAGE(IF(($A$2:$A$7=$A13)*LEN(B$2:B$7),B$2:B$7))}')><FONT FACE=Arial COLOR=#000000>2.333</FONT></A></TD><TD BGCOLOR=#FFFFFF ALIGN=Right VALIGN=BOTTOM ><A HREF=javascript:alert('{=AVERAGE(IF(($A$2:$A$7=$A13)*LEN(C$2:C$7),C$2:C$7))}')><FONT FACE=Arial COLOR=#000000>2.500</FONT></A></TD><TD BGCOLOR=#FFFFFF>
</TD></TR><TR><TD COLSPAN=5><U>Hoja1</U></TD></TR></TABLE>
<FONT COLOR=#339966>To see the formula in the cells just click on the cells hyperlink</FONT>
<FONT COLOR=#339966 SIZE=1>The above image was automatically generated by [HtmlMaker V1.28]</FONT>
<FONT COLOR=#339966 SIZE=1>If you want FREE SOFT, <A HREF=mailto:corosuke@chan.co.jp>click here</A> and Colo will email the file to you</FONT>
<FONT COLOR=#339966 SIZE=1>This code was graciously allowed to be modified: by <A HREF=mailto:ivanmoala@xtra.co.nz>Ivan F Moala</A> All credit to Colo</FONT>
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