IAS 16 PPE

Hi Chris, Thank you for your lecture series on F1. I was working out an example from my course book and am struggling out here. Please guide. Q. An entity purchased a property 15 years ago at a cost of $100,000 and has depreciated it at a rate of 2% per annum ,using straight line basis. The entity had the property professionally valued at $ 500,000. What is the revaluation surplus that would be recorded in the financial statements in respect of this property. My working Historic cost -100,000 Depreciation - 2% @15 years- 2000*15=30,000 Revaluation -500000. So carrying value has moved from (100,000-30,000)=70,000 to 500,000 hence difference is 430,000 to OCI hence the journal entry would be Dr. Asset- 400,000 (500K$-100K$) Dr. Accumulated depreciation 30,000 Cr. Revaluation surplus 430,000 The answer in the textbook is 530,000. Please help.