pre_text: Intellectual Property and Custom Development Income Licensing of intellectual property including royalty-based fees decreased 49.2 percent in 2019 compared to 2018. This was primarily due to a decline in new partnership agreements compared to the prior year. The timing and amount of licensing, sales or other transfers of IP may vary significantly from period to period depending upon the timing of licensing agreements, economic conditions, industry consolidation and the timing of new patents and know-how development.
table: ($ in millions) Percent
table: For the year ended December 31: 2019 2018 Yr.-to-Yr. Percent Change
table: Licensing of intellectual property including royalty-based fees $367 $723 (43.2)%
table: Custom development income 246 275 (10.5)
table: Sales/other transfers of intellectual property 34 28 22.6
table: Total $648 $1,026 (36.9)%
question: Analyse this data from a financial earnings document. What was the increase / (decrease) in the Custom development income from 2018 to 2019?