Notes on similarities, differences, and patterns you see across all companies, your ideas on potential explanations for these, and your recommendation on the best company to invest in.

Describe the depreciation methods used.

1. Suncor Energy Inc

Once properties have been explored and evaluated and production has started, the cost of Exploration and Evaluation is transferred to Property, Plant, and Equipment and is depreciated using the unit-of-production method. The exception to this is exploration and evaluation costs associated with oilsands mines, as well as costs to develop and construct the mines, which are depreciated using the straight-line method. Capital expenditure costs are depreciated using the straight-line method over a period of 2 to 5 years. Right-of-use assets are depreciated using the straight-line method.
Depreciation methods are reviewed annually or when events happen that effect depreciation in any way.

2. Amplify Energy Corp

The receivable turnover ratio has been declined to 7.90 which shows that the revenue of the organization has been declined significantly. The company is using SLM method and depreciation is charged over the estimated useful life of assets.

3. Ultra Petroleum Corporation

The declining-balance method is the depreciation method Ultra Petroleum uses. This method involves multiplying the book value at the beginning of the period by the depreciation rate. This method implies that the PP&E used by Ultra Petroleum are most efficient in the beginning years of use

4. Nabors Industries Ltd

Nabors uses the Units of Production method to provide for the depreciation of the drilling rigs. For each day a rig is operating, it depreciates over a 4,927day period. Depreciation on their buildings, oilfield hauling, and mobile equipment are made using the straight-line method.