Cumulative backlog to date

[andrew_hardwick]

I am trying to create a line graph in Power BI to show the difference between a number of opened tickets vs resolved tickets on a daily basis. I then want to show a line graph of the cumulative data.

I am new to Power BI and whilst I can easily achieve this in Excel, I cannot get what I need. The data is shown below from Excel. The Balance is the difference between Opened and Resolved and then each day it either increases or decreased based on this difference.

Date	Opened	Resolved	Balance
18/04/2016	52	35	17
19/04/2016	62	47	32
20/04/2016	111	91	52
21/04/2016	130	103	79
22/04/2016	141	96	124
23/04/2016	6	0	130
24/04/2016	8	1	137
25/04/2016	108	80	165
26/04/2016	101	88	178
27/04/2016	73	71	180
28/04/2016	69	55	194
29/04/2016	93	100	187
30/04/2016	4	0	191
01/05/2016	2	0	193
02/05/2016	3	1	195
03/05/2016	85	97	183
04/05/2016	68	98	153
05/05/2016	60	75	138
06/05/2016	73	80	131
07/05/2016	3	0	134

The raw data I have is as below, where the Incident Number is a unique reference