CSV data does not recognize column as numbers when contains negative numbers

Anonymous and kcantor Thansk for your support.

Incorrect characters is the first thing I excemined. There are no spaces in the input and the minus is ASCII 2D when viewed with a HEX editor. I have unsuccesfulyy tried to generate a csv in unicode with the minus as U+2212 in PowerShell.

When using PowerBI desktop, every test set I have is imported correct as numbers, neg and pos combined.
But I realy want to accomplish this in PowerBI Service (Web) because I am creating an auto updated Dashboard with input from various powershell scripts. I am doing this via CSV's on Onedrive for business, which automaticaly update the dataset when the CSV is changed.

j_bujnowski Maybe my testing can help you.
Testsets I used and their results

• only positive numbers - Column imported as numbers
• change one number to negitive - Column changed to string
• only negative numbers - Column imported as numbers
• change one number to positive- Column stays as numbers
• random mix of neg and pos - Column imported as string
• Specific mix of neg and pos, starting with 10 neg - Column imported as numbers

I believe Microsoft has a funny algortihem to interpet numbers.
This is so frustrating that I moved away from this solution and am investigating the use of PowerBI API.
This gives me more controle over the column type definition and as a bonus the possibility to directly update data from powershell and bypass Ondedrive.  With PowerBIPS in powershell via PowerBI API I created a dataset with a int64 column and have now succesfully loaded mixed neg and pos numbers.

Thies does not solve the issue here but it seems a better solution for me.