pre_text: NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (in thousands, except for share and per share data) Our pension plan asset allocation at December 31, 2019, and 2018, and target allocation for 2020 by asset category are as follows: We employ a liability-driven investment strategy whereby a mix of equity and fixed-income investments are used to pursue a derisking strategy which over time seeks to reduce interest rate mismatch risk and other risks while achieving a return that matches or exceeds the growth in projected pension plan liabilities. Risk tolerance is established through careful consideration of plan liabilities and funded status. The investment portfolio primarily contains a diversified mix of equity and fixed-income investments. Other assets such as private equity are used modestly to enhance long-term returns while improving portfolio diversification. Investment risk is measured and monitored on an ongoing basis through quarterly investment portfolio reviews, annual liability measurements, and asset/liability studies at regular intervals.
table: Target Allocations Percentage of Plan Assets at December 31,
table: Asset Category 2020 2019 2018
table: Equity securities 13% 13% 12%
table: Debt securities 83% 83% 84%
table: Other 4% 4% 4%
table: Total 100% 100% 100%
question: Analyse this data from a financial earnings document. What was the change in the percentage of plan assets for Equity Securities between 2018 and 2019?