Auto Depreciation with Bonus

I have a question regarding auto depreciation. I bought a vehicle ($54,500) and put into service 1/1/23. For my 2023 taxes I elected bonus depreciation. I use the vehicle 80% business so I got 80% of $20,200 or $16,160 for 2023 depreciation. $54,500 x80% = $43,600 - $16,160 = $27,440 remaining.

Now starting my 2024 taxes and transferring the info from 2023. Same 80% business use. Turbo Tax says my federal depreciation is $2,790. I do not see how this is calculated but I thought it would be using the 5 yr MACRS $27,440 x .4 = $10,976. What am I doing wrong?

Also, as a test, I changed my 2023 return to not accept bonus depreciation so that I got $54,500 x 80% x .2 (first year for a total of $8,720 depreciation and a remainder of $43,600 - $8,720 = $34,880

When I transfer that info to 2024, then Turbo Tax calculates year 2 as $34,880 x .4 = $13,952 as expected.

Why is year 2 after bonus depreciation in year 1 not calculated the same way? Any ideas?

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