pre_text: The GBS profit margin increased 0.9 points to 27.7 percent and pre-tax income of $1,666 million increased 2.2 percent year to year. The pre-tax margin of 9.9 percent increased slightly year to year. The year-to-year improvements in margins and pre-tax income were driven by the continued mix shift to higher-value offerings, the yield from delivery productivity improvements and a currency benefit from leveraging the global delivery resource model. We continued to invest in our services offerings and skills necessary to assist our clients on their cloud journey. * Recast to reflect segment changes.
table: ($ in millions)
table: For the year ended December 31: 2019 2018* Yr.-to-Yr. Percent/ Margin Change
table: Global Business Services
table: External gross profit $4,606 $4,448 3.5%
table: External gross profit margin 27.7% 26.8% 0.9 pts.
table: Pre-tax income $1,666 $1,629 2.2%
table: Pre-tax margin 9.9% 9.6% 0.2 pts.
question: Analyse this data from a financial earnings document. What was the increase / (decrease) in the Pre-tax income from 2018 to 2019?