Direct costs in the fourth quarter of 2019 were $79.1 million, or 79.6% of revenue, compared with $78.5 million, or 80.7% of revenue, in the third quarter of 2019, and $75.4 million, or 81.0% of revenue, in the fourth quarter of 2018. SG&A expense in the fourth quarter of 2019 was $17.7 million, which included $0.6 million in acquisition-related costs associated with Soft Company andTech-IT. This compared with $17.2 million of expenses in the third quarter of 2019, which included $0.8 million in acquisition-related costs. SG&A expense in the fourth quarter of 2018 was $18.5 million, which included $0.5 million in acquisition-related costs and $0.7 million in severance-related charges.
Operating income in the fourth quarter of 2019 was $2.5 million, or 2.5% of revenue, and included the previously referenced acquisition-related costs. Excluding acquisition-related expenses,non-GAAP operating income was $3.1 million, or 3.1% of revenue. Operating income in the third quarter of 2019 was $1.5 million, or 1.6% of revenue, and included acquisition-related costs. Excluding acquisition-related expenses,non-GAAP operating income in the third quarter of 2019 was $2.3 million, or 2.4% of revenue. Operating loss in the fourth quarter of 2018 was $0.8 million, or (0.8%) of revenue, and included acquisition-related and severance expenses. Excluding acquisition-related and severance expenses,non-GAAP operating income in the fourth quarter of 2018 was $0.4 million, or 0.4% of revenue. CTG’s operations outside of the U.S. are conducted in local currencies. Accordingly, fluctuations in currency valuation for the countries in which the Company operates generally have minimal impact on operating results; these fluctuations reduced operating income by less than $0.1 million in the fourth quarter of 2019.
Net income in the fourth quarter of 2019 was $1.7 million, or $0.12 per diluted share, which included $0.3 million, or $0.02 per diluted share, in acquisition-related expenses. Net income in the third quarter of 2019 was $0.9 million, or $0.06 per diluted share, which included $0.5 million, or $0.04 per diluted share, in acquisition-related expenses. Net loss in the fourth quarter of 2018 was $5.3 million, or ($0.39) per share, which included $0.9 million, or $0.06 per share, in acquisition-related and severance expenses, and $0.36 per diluted share intax-related items.
CTG’s effective income tax rate in the fourth quarter of 2019 was 34.0% compared with 33.5% in the third quarter of 2019. The Company’s effective tax rate in the fourth quarter of 2018 was 449%, which reflected a reserve for the U.S. deferred tax assets of $3.8 million, costs under the Global IntangibleLow-Taxed Income (GILTI) provisions of the 2017 Tax Cuts and Jobs Act totaling $0.7 million, andnon-deductible acquisition-related costs in the Company’s foreign operations for the acquisition of Soft Company.
Consolidated Full Year Results
For the full year 2019, revenue was $394.2 million, compared with $358.8 million in 2018. Currency translation had a negative impact of $8.4 million on revenue in 2019, compared with currency translation benefit of $4.9 million in 2018. Direct costs in 2019 were $319.1 million, or 81.0% of revenue, compared with $290.3 million, or 80.9% of revenue in 2018. SG&A expense in 2019 was $68.0 million, and included $2.3 million in acquisition related costs, compared with $66.4 million in 2018, which included $2.0 million in acquisition related costs and $0.7 million in severance-related charges.
Operating income for the full year 2019 was $7.0 million, which included $2.3 million of acquisition-related expenses. This compared with operating income of $2.1 million in 2018, which included $2.0 million of acquisition-related expenses and $0.7 million of severance-related charges. GAAP net income for 2019 was $4.1 million, or $0.29 per diluted share, which included acquisition-related expenses of $0.11 per share. This compared with a GAAP net loss in 2018 of $2.8 million, or ($0.20) per share, which included anon-taxable life insurance gain of $0.06 per share, acquisition-related expenses of $0.10 per share, severance of $0.04 per share, a $0.29 per sharenon-cash charge related to reserves for U.S. deferred tax assets, and othertax-related items of $0.07 per share.
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