Regression node - x(time) format

exporttest3.txt (2.5 MB)
Hi there,
I am trying to use the node-red-contribution-regression node.
My x values are date time coming from a flow.
In which format should I feed the data/time to the regression node?
At present my date time format is 2021-09-24 18:01:04.919
But if I use it in such format, I keep getting y=0x+27.89

I noted that passing only the time (18:01:04.919) the regression node is working but since my data includes also year-month-day, I need to pass also this part. At least month-day in addition to the time.
Another unexpected thing I am experiencing is that such node will start outputting NaN values for Y as soon as a couple of hundred values are computed and the formula starts compiling. I have 36000 points to evaluate. I did try to set the data set size to 36000 but the behaviour doesn't change.

Any hint?

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Try converting the date/time to valid ISO format. So something like
2021-11-12T07:41:53+00:00
where the +00:00 on the end is the timezone offset.

Thanks Colin, I am busy trying that but meanwhile I discovered another major thing I do not understand. I have updated my post and also given the data set as attachment. Just in case someone likes to test it.

Are you sure it is the amount of data and not a bad sample in there somewhere?
I suggest that you find the smallest set of data that fails, not thousands of lines, and then post an issue on the node's github page.

If you do that post a link to the issue here for anyone that finds the thread.

Will do. However if I import the data in excel, no issues there. I will double check. Thanks