I want to produce a cumulative line chart for the period 201706 to 201801. But I'm not certain to generate a a cumulative line chart. Till 2017 the data is in increasing order (e.g. 0.0 in 201706,0.18 in 201707 .....3.04 in 201712 ).
But in 201801 the data has a value 0.0 and the chart has dropped down for that period.But for that period I need the chart as highlighted in red. Appreciate if someone of you help me to do the cumulative sum to resolve the error.