a question about SUM function

[Ms.Sigma]

Hello all,

I want to ask a question concerning how to sum data of a series based on different horizon. for example, I have following data:

Date Data

2000-1-1 1
2000-1-2 2
2000-1-3 3
2000-1-4 4
2000-1-5 5
2000-1-6 6
...
2000-1-31 31

Date series are in the column A, and Data series are in the column B.

I want to get the sum of each 3 or 5 or 10 data of Column B. In other words, based on 3-day horizon, the value of column D will be: D1=sum(B2:B4), D2=sum(B5:B7), and so on. What is the correct function to achieve this goal?

May I also have a new date series for the corresponding new data in column D? It is assumed that the new date series are in Column C. For example, since cell D1 is the sum of B2 to B4, thus, the date value of C1 should be 2000-1-3.

Thanks a lot for your help!

 

[Ganjin]

<TABLE style="WIDTH: 282pt; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 width=375 border=0><COLGROUP><COL style="WIDTH: 64pt; mso-width-source: userset; mso-width-alt: 3108" width=85><COL style="WIDTH: 48pt" width=64><COL style="WIDTH: 85pt; mso-width-source: userset; mso-width-alt: 4132" span=2 width=113><TBODY><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 64pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right width=85 height=20>2000-01-01

</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext; WIDTH: 48pt; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right width=64>1</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext; WIDTH: 85pt; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right width=113>2000-01-03</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext; WIDTH: 85pt; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right width=113>6</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-02</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-06</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>15</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-03</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>3</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-09</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>24</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-04</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>4</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-12</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>33</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-05</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>5</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-15</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>42</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-06

</TD><TD class=xl65 id=td_post_2662200 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>6</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-18</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>51</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-07</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>7</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>2000-01-21</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>60</TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-08</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>8</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-09</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>9</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-10</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>10</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-11</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>11</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-12</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>12</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-13</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>13</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-14</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>14</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-15</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>15</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-16</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>16</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-17</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>17</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-18</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>18</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-19</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>19</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-20</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>20</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 15pt; BACKGROUND-COLOR: transparent" align=right height=20>2000-01-21</TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right>21</TD><TD class=xl64 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD><TD class=xl65 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent"> </TD></TR></TBODY></TABLE>formula in C1:
=INDEX(A:A,3*(ROW()),0)
formula in D1:
=SUM(OFFSET($B$1,3*(ROW()-1),0):OFFSET($B$3,3*(ROW()-1),0))

 

[Ms.Sigma]

Thanks Ganjin!

the function for cell D1 achieve my goal, but it seems there is some problem about function for cell C1. After inputing the function, the value appeared in column C is not date. Could you please give me further instruction? Many thanks again!!

 

[Ms.Sigma]

I know my mistake now. I forgot to change the data type of Column C.