Our profit recognition related to construction contracts is based on estimates of transaction price and costs to complete each project. These estimates can vary significantly in the normal course of business as projects progress, circumstances develop and evolve, and uncertainties are resolved. Changes in estimates of transaction price and costs to complete may result in the reversal of previously recognized revenue if the current estimate adversely differs from the previous estimate. When we experience significant changes in our estimates, we undergo a process that includes reviewing the nature of the changes to ensure that there are no material amounts that should have been recorded in a prior period rather than as revisions in estimates for the current period. For revisions in estimates, generally we use the cumulative catch-up method for changes to the transaction price that are part of a single performance obligation. Under this method, revisions in estimates are accounted for in their entirety in the period of change. There can be no assurance that we will not experience further changes in circumstances or otherwise be required to revise our estimates in the future. Other than those identified in the 2019 Annual Report on Form 10-K, we did not identify any material amounts that should have been recorded in a prior period for the three months ended March 31, 2019. In our review of these changes for the three months ended March 31, 2020, we did not identify any material amounts that should have been recorded in a prior period.

In the normal course of business, we have revisions in estimates, including estimated costs some of which are associated with unresolved affirmative claims and back charges. The estimated or actual recovery related to these estimated costs may be recorded in future periods or may be at values below the associated cost, which can cause fluctuations in the gross profit impact from revisions in estimates.

There were no increases from revisions in estimates, which individually had an impact of $5.0 million or more on gross profit, for the periods presented.

The projects with decreases from revisions in estimates, which individually had an impact of $5.0 million or more on gross profit are summarized as follows (dollars in millions except per share data):

Decreases during the three months ended March 31, 2020 and 2019 were due to additional costs from differing site conditions and construction delays. One project had a decrease in our Specialty segment during the three months ended March 31, 2020 and the remaining decreases during both the three months ended March 31, 2020 and 2019 were in our Transportation segment.