(1) optimize the long-term return on plan assets at an acceptable level of risk and manage projected future cash contributions; (2) maintain a broad diversification across asset classes and among investment managers; and (3) manage the risk level of the plans' assets in relation to the plans' liabilities. Each plan's respective allocation targets promote optimal expected return and volatility characteristics given a focus on a long-term time horizon for fulfilling the plans' obligations. All assets are managed by external investment managers with a mandate to either match or outperform their benchmark. The plans used different asset managers in the U.S., U.K. and Canada and each plan's respective asset allocation could be impacted by a change in asset managers. Our investment strategies for our defined benefit pension plans also consider the funding status for each plan. For defined benefit pension plans that are highly funded, assets are invested primarily in fixed income holdings that have a similar duration to the associated liabilities. For plans with lower funding levels, the fixed income component is managed in a similar manner to the highly funded plans. In addition to this liability- matching fixed income allocation, these plans also contain exposure to return generating assets including: equities, real estate, debt, and other investments held with the goal of producing higher returns, which may also have a higher risk profile. These investments are diversified by investing globally with limitations placed on issuer concentration. Both our U.K. and Canadian plans hedge a portion of the foreign exchange exposure between plan assets that are not denominated in the local plan currency and the local currency as the Canadian and U.K. pension liabilities will be settled in CAD and GBP, respectively. The following compares target asset allocation percentages with actual asset allocations on a weighted-average asset basis as of December 31, 2018: Target Allocations Significant Concentration Risks Valuation Techniques During the first quarter of 2019, we adjusted our target allocation of plan assets to align with our updated investment strategy. These allocation changes are reflected in our weighted-average EROA assumptions for 2019. We periodically evaluate our defined benefit pension plan assets for concentration risks. As of December 31, 2018, we did not have any individual underlying asset position that composed a significant concentration of each plan's overall assets. However, we currently have significant plan assets invested in U.K., U.S. and Canadian government fixed income holdings. A provisional credit rating downgrade for any of these governments could negatively impact the asset values. Further, as our benefit plans maintain exposure to non-government investments, a significant system-wide increase in credit spreads would also negatively impact the reported plan asset values. In general, equity and fixed income risks have been mitigated by company-specific concentration limits and by utilizing multiple equity managers. We do have significant amounts of assets invested with individual fixed income and hedge fund managers, therefore, the plans use outside investment consultants to aid in the oversight of these managers and fund performance. We use a variety of industry accepted valuation techniques to value our plan assets. The techniques vary depending upon instrument type. Whenever possible, we prioritize the use of observable market data in our valuation processes. We use market, income and cost approaches to value our plan assets as of period end. See  Note 1, "Basis of Presentation and Summary of Significant Accounting Policies"  for additional information on our fair value methodologies and accounting policies. We have not changed our fair value techniques used to value plan assets this year. 141 Target allocations Actual allocations Equities 14.4% 13.1% Fixed income 67.1% 70.9% Real estate 2.6% 2.5% Annuities 9.6% 9.7% Other 6.3% 3.8%