Calculating Deprecation with land

[Andrew Shippy]

I ask this questions because every post or online forum about this makes it seem like the value of the land is between 15-25% of the costs basis, but when I calculate it in my scenario below you can see the land is near 40% of the cost basis. I just want to make sure I am accurate when calculating the depreciated value on my property. 

When calculating deprecation on my property and taking in the cost basis, I understand you need to subtract the costs of the land from the property itself. So, looking at the below example if my cost basis was 131,000, would I need to deduct the below land value of $51,000 from my that amount. Meaning my depreciated value would be $80,000/27.5=2,909 straight line. 

I know I should seek a professional, but figured someone on here would be more knowledge than myself. 

FY18/19 ASSESSMENT

LAND VALUE	$51,000
IMPROVEMENT VALUE	$89,700
TOTAL VALUE	$140,700

I know I should seek a professional, but figured someone on here would be more knowledgeable than myself.