One way ..

Assuming source data in cols A and B from row1 down

Put in C1: =$A$1+ROW(A1)-1
Put in D1: =SUMIF(A:A,C1,B:B)
Put in E1: =SUM(OFFSET(D1,,,10))
Select C1:E1, fill down as far as required

Col C simply lists all milepoints, starting from the milepoint in A1
Col D returns the total accidents at each milepoint in col C
Col E yields the required total accidents for the 10 mile stretch
for each milepoint in col C, viz.:
E1 gives the figure for milepoints 141-150
E2 gives the figure for milepoints 142-151
E2 gives the figure for milepoints 143-152
and so on ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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wrote in message
oups.com...
I have road milepoints and the number of accidents at that milepoint in
format listed below. What I need to do is find the 10-mile stretch of
road with the most accidents. How do I have Excel go through and take a
number from the left column and sum all the accidents within a 10-mile
range?

141 1
142 1
143 1
146 1
147 1
149 1
151 1
155 1
158 1
159 1
161 1
163 1
166 2
167 3
167 1
173 1
175 1
175 1
175 1
177 1
178 1
179 1
180 1
180 1
180 1
182 1
183 1
185 1