Cant add more data points to numbers chart

Question

I have a 2 axis 2D graph. I would guess i have about 150 data points along the y axis for both lines on the chart. I have been updating the chart each week no probem with new data points. However today, i can only seem to add a few more points - when i try to add past a certain amount of data points, the last 20 or so data points are removed from the series?
It simply will not allow me to add more data?
Any help on this matter would be greatly appreciated as the charts are for use in my business

Answer 1

Hi Jerrold, thanks for the reply.
I dont have category labels. I have a 2 axis 2D chart, with a line series and an area series on the chart. I add new data to the chart each week by clicking on either the line or the area series on the chart, then going to my data table beside the chart, and by holding apple command button and clicking on the relevant cells to add to the charts. As of this weeks adding, it starts of as usual, adding the cells to the line and area series, and thus adding data onto the existing chart and extending it out to the right, as it normally would. However, i can only add a certain amount of new cells (data points) to either the line or area series. When i go to add more, a very strange thing happens. The series switches from all the cells that are highlighted blue, to another table i have on the same document??? If i look at the Inspector in the Data box under the series tab, the data goes from the typical 'Table 1 :: D18', (highlighted in blue, to the following weird data point : 'D38,SFTGlobalID_CB7D88F601784CAC8DD283ECA59CFB41 :'
Its worth noting that although i an working on a brand new macbook pro, numbers has crashed on me a number of times when adding large amounts of data to the chart The table has 1,120 rows, and 11 columns. Only 1 in every 5 or so rows are plotted (on y axis), so roughly 200 or so data points for both line and area chart are plotted. And only 1 column is used for each chart. Thus i have 11 charts on the one numbers document. Is it a case of too much for numbers to handle?
I have just deleted all the y axis data for the area series for one chart, and added all the data from the whole table again, (rather than just adding this weeks to last weeks, which is where i saw the problem in the first place) to see if it made a difference. But none. Once i got to a certain point, if i add one more cell data point to the chart, the exact same thing happened as above - the highlighted data switched from what i had been highlighting the whole way down the table, to an entirely different table in the same workbook.
Any ideas would be greatly appreciated.