Numerous calculation errors with addition and subtraction in Calc

[Talyvar]

Hello,
I have found calculation errors when using addition and subtraction in columns.

Second row is the starting number, here 40.
In each column I am adding or subtracting by the number listed in the column header.
(one of: 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1)

The formula is simple. Take cell directly above and + or - the fixed amount.
Sample formula: =C2-0.8

There are 1000 rows of calculations.
Each cell is expanded to see 20 decimal places.

Numerous errors can be seen, all highlighted in light yellow.
Using 1 and 0.5 give no errors. All others give errors are various places.

Settings are default.
New sheets used.
No formatting done, except cell borders.

Spreadsheet is attached.

I would appreciate any help in eliminating these errors.
Thank you.
Testing Calculation Errors.ods (245.3 KB)

[robleyd]

Calc: Accuracy problem

[Talyvar]

Thank you for that. I had no idea such an issue was present. I find it fascinating, especially as a non-coder.

In a quick test (to help others who may read this), using ROUND, I noticed that as long as I reduce the decimal places to 12 or less, the result looks correct (still at 20 decimal places). 13 or above still gives errors.

While I can not state that this would correct this issue in all circumstances, it is sufficient for my needs, and I suspect most user’s needs.

Thanks again for the link. I will consider this issue solved.