Column A contains week numbers starting at Week Number 0
(ROW()-1) to a Week Number "n" and if the week number
exceeds the numbers of weeks ROW()-1 returns ZERO.

Column B contains a value related to a week Number.

I want to be able to produce a graph that the source data
references any value in Column B if Column A is
between "Zero" and the next 'Zero"

Had a try with the HLOOKUP function within the data
source but with no luck

An example of the data is below...

Week No, Value
0    0.0
1    1.0
2    2.0
3    3.0
4    4.0
5    5.0
6    6.0
7    7.0
8    8.0
9    9.0
10    10.0
11    10.0
12    10.0
13    10.0
14    10.0
15    10.0
16    10.0
17    10.0
18    8.3
19    6.7
20    5.0
21    3.3
22    1.7
23    0.0
24    0.0
0    0.0
0    0.0
0    0.0