We have offices in various locations throughout the world. Substantially all of our offices are located in leased premises. We maintain our corporate headquarters at 122 Leadenhall Street, London, England, where we occupy approximately 195,000 square feet of space under an operating lease agreement that expires in 2034. The following are additional significant leased properties, along with the occupied square footage and expiration.
Due to the factors set forth above, net income from continuing operations was $1,574 million in 2019, an increase of $474 million, or 43%, from 2018.
Organic revenue growth, a non-GAAP measure defined under the caption “Review of Consolidated Results - Organic Revenue Growth,” was 6% in 2019, compared to 5% organic growth in the prior year. Organic revenue growth was driven by growth across every major revenue line, with particular strength in Reinsurance Solutions and Commercial Risk Solutions.
Net loss from discontinued operations was $1 million in the twelve months ended December 31, 2019, compared to net income from discontinued operations of $74 million in 2018.
Translating prior year results at current year foreign currency exchange rates, currency fluctuations had a $0.19 unfavorable impact on net income per diluted share during the year ended December 31, 2019. Currency fluctuations had a $0.08 favorable impact on net income per diluted share during the year ended December 31, 2018, when 2017 results were translated at 2018 rates. Currency fluctuations had a $0.12 favorable impact on net income per diluted share during the year ended December 31, 2017, when 2016 results were translated at 2017 rates.
As of December 31, 2019, we had two primary committed credit facilities outstanding: our $900 million multi-currency U.S. credit facility expiring in February 2022 and our $400 million multi-currency U.S. credit facility expiring in October 2023.
Compensation expense is recognized over the performance period. The number of shares issued on the vesting date will vary depending on the actual performance objectives achieved, which are based on a fixed number of potential outcomes. We make assessments of future performance using subjective estimates, such as long-term plans. As a result, changes in the underlying assumptions could have a material impact on the compensation expense recognized.
Note 2 “Summary of Significant Accounting Principles and Practices” of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report contains a summary of our significant accounting policies, including a discussion of recently issued accounting pronouncements and their impact or future potential impact on our financial results, if determinable.
As discussed in Note 11 “Income Taxes” of the Notes to Consolidated Financial Statements, the Company had net deferred tax assets of $446 million at December 31, 2019. Deferred tax assets are reduced by a valuation allowance if, based on the weight of all available evidence, in management’s judgment it is more likely than not that some portion, or all, of the deferred tax assets will not be realized.
In August 2017, the FASB issued new accounting guidance related to targeted improvements to accounting for hedging activities. The new guidance amended its hedge accounting model to enable entities to better portray their risk management activities in the financial statements. The guidance eliminated the requirement to separately measure and report hedge ineffectiveness and required the effect of a hedging instrument to be presented in the same income statement line as the hedged item. The new guidance was effective for Aon in the first quarter of 2019 and the Company adopted it on a modified retrospective basis with no cumulative effect adjustment to Accumulated other comprehensive income (loss) or corresponding adjustment to Retained earnings. Changes
Each of these facilities includes customary representations, warranties, and covenants, including financial covenants that require Aon to maintain specified ratios of adjusted consolidated EBITDA to consolidated interest expense and consolidated debt to adjusted consolidated EBITDA, in each case, tested quarterly. At December 31, 2019, Aon did not have borrowings under either credit facility, and was in compliance with the financial covenants and all other covenants contained therein during the twelve months ended December 31, 2019.
The impact of the Tax Reform Act including the Transition Tax, the re-measurement of U.S. deferred tax assets and liabilities from 35% to 21%, withholding tax accruals, and the allocation of tax benefit between continuing operations and discontinued operations related to utilization of foreign tax credits.
Based on current assumptions, in 2020, the Company expects to contribute approximately $5 million, $99 million, and $19 million to its significant U.K., U.S., and other major pension plans, respectively.
The Company has certain contractual contingent guarantees for premium payments owed by clients to certain insurance companies. The maximum exposure with respect to such contractual contingent guarantees was approximately $110 million at December 31, 2019, compared to $103 million at December 31, 2018.