diff --git a/packages/@ourworldindata/grapher/src/chart/ChartDimension.ts b/packages/@ourworldindata/grapher/src/chart/ChartDimension.ts
index 370cc10327..c5af906e29 100644
--- a/packages/@ourworldindata/grapher/src/chart/ChartDimension.ts
+++ b/packages/@ourworldindata/grapher/src/chart/ChartDimension.ts
@@ -13,6 +13,7 @@ import {
     OwidVariableDisplayConfig,
     OwidChartDimensionInterface,
     Time,
+    OwidChartDimensionInterfaceWithMandatorySlug,
 } from "@ourworldindata/utils"
 import { OwidTable, CoreColumn } from "@ourworldindata/core-table"
 
@@ -35,9 +36,17 @@ export interface LegacyDimensionsManager {
     table: OwidTable
 }
 
+export function getDimensionColumnSlug(
+    variableId: OwidVariableId,
+    targetYear: Time | undefined
+): ColumnSlug {
+    if (targetYear) return `${variableId}-${targetYear}`
+    return variableId.toString()
+}
+
 export class ChartDimension
     extends ChartDimensionDefaults
-    implements Persistable
+    implements Persistable, OwidChartDimensionInterfaceWithMandatorySlug
 {
     private manager: LegacyDimensionsManager
 
@@ -78,7 +87,16 @@ export class ChartDimension
     }
 
     // Do not persist yet, until we migrate off VariableIds
-    @observable slug?: ColumnSlug
+    @observable _slug?: ColumnSlug | undefined
+
+    @computed get slug(): ColumnSlug {
+        if (this._slug) return this._slug
+        return getDimensionColumnSlug(this.variableId, this.targetYear)
+    }
+
+    set slug(value: ColumnSlug | undefined) {
+        this._slug = value
+    }
 
     @computed get column(): CoreColumn {
         return this.table.get(this.columnSlug)
diff --git a/packages/@ourworldindata/grapher/src/core/Grapher.tsx b/packages/@ourworldindata/grapher/src/core/Grapher.tsx
index 8cb3ef69cd..08632a43db 100644
--- a/packages/@ourworldindata/grapher/src/core/Grapher.tsx
+++ b/packages/@ourworldindata/grapher/src/core/Grapher.tsx
@@ -140,6 +140,7 @@ import { loadVariableDataAndMetadata } from "./loadVariable"
 import Cookies from "js-cookie"
 import {
     ChartDimension,
+    getDimensionColumnSlug,
     LegacyDimensionsManager,
 } from "../chart/ChartDimension"
 import { TooltipManager } from "../tooltip/TooltipProps"
@@ -191,11 +192,7 @@ import {
     DefaultChartClass,
 } from "../chart/ChartTypeMap"
 import { Entity, SelectionArray } from "../selection/SelectionArray"
-import {
-    addSelectedEntityColorsToTable,
-    computeActualDimensions,
-    legacyToOwidTableAndDimensions,
-} from "./LegacyToOwidTable"
+import { legacyToOwidTableAndDimensions } from "./LegacyToOwidTable"
 import { ScatterPlotManager } from "../scatterCharts/ScatterPlotChartConstants"
 import {
     autoDetectSeriesStrategy,
@@ -1151,19 +1148,20 @@ export class Grapher
         // TODO grapher model: switch this to downloading multiple data and metadata files
 
         const startMark = performance.now()
-        const table = legacyToOwidTableAndDimensions(
+        const dimensions = legacyConfig.dimensions?.map((dimension) => ({
+            ...dimension,
+            slug:
+                dimension.slug ??
+                getDimensionColumnSlug(
+                    dimension.variableId,
+                    dimension.targetYear
+                ),
+        }))
+        const tableWithColors = legacyToOwidTableAndDimensions(
             json,
-            legacyConfig.dimensions ?? []
+            dimensions ?? [],
+            legacyConfig.selectedEntityColors
         )
-        const tableWithColors = legacyConfig.selectedEntityColors
-            ? addSelectedEntityColorsToTable(
-                  table,
-                  legacyConfig.selectedEntityColors
-              )
-            : table
-        const dimensions = legacyConfig.dimensions
-            ? computeActualDimensions(legacyConfig.dimensions)
-            : []
         this.createPerformanceMeasurement(
             "legacyToOwidTableAndDimensions",
             startMark
@@ -1173,10 +1171,6 @@ export class Grapher
             this.inputTable = inputTableTransformer(tableWithColors)
         else this.inputTable = tableWithColors
 
-        // We need to reset the dimensions because some of them may have changed slugs in the legacy
-        // transformation (can happen when columns use targetTime)
-        this.setDimensionsFromConfigs(dimensions)
-
         this.appendNewEntitySelectionOptions()
 
         if (this.manager?.selection?.hasSelection) {
diff --git a/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.test.ts b/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.test.ts
index 2766a107bb..a6bd3265a0 100755
--- a/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.test.ts
+++ b/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.test.ts
@@ -6,17 +6,40 @@ import {
     OwidTableSlugs,
     StandardOwidColumnDefs,
     LegacyGrapherInterface,
+    OwidChartDimensionInterface,
 } from "@ourworldindata/types"
-import { ColumnTypeMap, ErrorValueTypes } from "@ourworldindata/core-table"
 import {
-    addSelectedEntityColorsToTable,
-    legacyToOwidTableAndDimensions,
-} from "./LegacyToOwidTable"
+    ColumnTypeMap,
+    ErrorValueTypes,
+    OwidTable,
+} from "@ourworldindata/core-table"
+import { legacyToOwidTableAndDimensions } from "./LegacyToOwidTable"
 import {
     MultipleOwidVariableDataDimensionsMap,
     OwidVariableDataMetadataDimensions,
     DimensionProperty,
 } from "@ourworldindata/utils"
+import { getDimensionColumnSlug } from "../chart/ChartDimension.js"
+
+export const legacyToOwidTableAndDimensionsWithMandatorySlug = (
+    json: MultipleOwidVariableDataDimensionsMap,
+    dimensions: OwidChartDimensionInterface[],
+    selectedEntityColors:
+        | { [entityName: string]: string | undefined }
+        | undefined
+): OwidTable => {
+    const dimensionsWithSlug = dimensions?.map((dimension) => ({
+        ...dimension,
+        slug:
+            dimension.slug ??
+            getDimensionColumnSlug(dimension.variableId, dimension.targetYear),
+    }))
+    return legacyToOwidTableAndDimensions(
+        json,
+        dimensionsWithSlug,
+        selectedEntityColors
+    )
+}
 
 describe(legacyToOwidTableAndDimensions, () => {
     const legacyVariableEntry: OwidVariableDataMetadataDimensions = {
@@ -46,9 +69,10 @@ describe(legacyToOwidTableAndDimensions, () => {
     }
 
     it("contains the standard entity columns", () => {
-        const table = legacyToOwidTableAndDimensions(
+        const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
             legacyVariableConfig,
-            legacyGrapherConfig.dimensions ?? []
+            legacyGrapherConfig.dimensions ?? [],
+            legacyGrapherConfig.selectedEntityColors
         )
         expect(table.columnSlugs).toEqual(
             expect.arrayContaining(
@@ -65,22 +89,27 @@ describe(legacyToOwidTableAndDimensions, () => {
 
     describe("conversionFactor", () => {
         it("applies the more specific chart-level conversionFactor", () => {
-            const table = legacyToOwidTableAndDimensions(legacyVariableConfig, [
-                {
-                    variableId: 2,
-                    display: { conversionFactor: 10 },
-                    property: DimensionProperty.y,
-                },
-            ])
+            const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
+                legacyVariableConfig,
+                [
+                    {
+                        variableId: 2,
+                        display: { conversionFactor: 10 },
+                        property: DimensionProperty.y,
+                    },
+                ],
+                legacyGrapherConfig.selectedEntityColors
+            )
 
             // Apply the chart-level conversionFactor (10)
             expect(table.rows[0]["2"]).toEqual(80)
         })
 
         it("applies the more variable-level conversionFactor if a chart-level one is not present", () => {
-            const table = legacyToOwidTableAndDimensions(
+            const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
                 legacyVariableConfig,
-                legacyGrapherConfig.dimensions ?? []
+                legacyGrapherConfig.dimensions ?? [],
+                legacyGrapherConfig.selectedEntityColors
             )
 
             // Apply the variable-level conversionFactor (100)
@@ -170,9 +199,10 @@ describe(legacyToOwidTableAndDimensions, () => {
             ],
         }
 
-        const table = legacyToOwidTableAndDimensions(
+        const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
             legacyVariableConfig,
-            legacyGrapherConfig.dimensions ?? []
+            legacyGrapherConfig.dimensions ?? [],
+            legacyGrapherConfig.selectedEntityColors
         )
 
         it("leaves ErrorValues when there were no values to join to", () => {
@@ -313,9 +343,10 @@ describe(legacyToOwidTableAndDimensions, () => {
             ],
         }
 
-        const table = legacyToOwidTableAndDimensions(
+        const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
             legacyVariableConfig,
-            legacyGrapherConfig.dimensions ?? []
+            legacyGrapherConfig.dimensions ?? [],
+            {}
         )
 
         it("shifts values in days array when zeroDay is is not EPOCH_DATE", () => {
@@ -436,9 +467,10 @@ describe(legacyToOwidTableAndDimensions, () => {
             ],
         }
 
-        const table = legacyToOwidTableAndDimensions(
+        const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
             legacyVariableConfig,
-            legacyGrapherConfig.dimensions ?? []
+            legacyGrapherConfig.dimensions ?? [],
+            legacyGrapherConfig.selectedEntityColors
         )
 
         it("duplicates 'day' column into 'time'", () => {
@@ -467,9 +499,10 @@ describe(legacyToOwidTableAndDimensions, () => {
                     chartTypes: [GRAPHER_CHART_TYPES.ScatterPlot],
                 }
 
-                const table = legacyToOwidTableAndDimensions(
+                const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
                     legacyVariableConfig,
-                    scatterLegacyGrapherConfig.dimensions ?? []
+                    scatterLegacyGrapherConfig.dimensions ?? [],
+                    legacyGrapherConfig.selectedEntityColors
                 )
 
                 expect(table.rows.length).toEqual(3)
@@ -625,9 +658,10 @@ describe("variables with mixed days & years with missing overlap and multiple po
         ],
     }
 
-    const table = legacyToOwidTableAndDimensions(
+    const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
         legacyVariableConfig,
-        legacyGrapherConfig.dimensions ?? []
+        legacyGrapherConfig.dimensions ?? [],
+        legacyGrapherConfig.selectedEntityColors
     )
 
     it("duplicates 'day' column into 'time'", () => {
@@ -644,9 +678,10 @@ describe("variables with mixed days & years with missing overlap and multiple po
 
     describe("join behaviour without target times is sane", () => {
         it("creates a sane table join", () => {
-            const table = legacyToOwidTableAndDimensions(
+            const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
                 legacyVariableConfig,
-                legacyGrapherConfig.dimensions ?? []
+                legacyGrapherConfig.dimensions ?? [],
+                legacyGrapherConfig.selectedEntityColors
             )
 
             // A sane join between years and days would create 5 days for the given input
@@ -766,11 +801,9 @@ describe("creating a table from legacy", () => {
         ...getLegacyGrapherConfig(),
         selectedEntityColors: { "Cape Verde": "blue" },
     }
-    const table = addSelectedEntityColorsToTable(
-        legacyToOwidTableAndDimensions(
-            getOwidVarSet(),
-            config.dimensions ?? []
-        ),
+    const table = legacyToOwidTableAndDimensionsWithMandatorySlug(
+        getOwidVarSet(),
+        config.dimensions ?? [],
         config.selectedEntityColors
     )
 
@@ -783,20 +816,20 @@ describe("creating a table from legacy", () => {
             "entityName",
             "entityId",
             "entityCode",
-            "entityColor",
             "year",
             "3512",
             "time", // todo: what is the best design here?
+            "entityColor",
         ])
 
         expect(table.columnNames).toEqual([
             "Entity",
             "entityId",
             "Code",
-            "entityColor",
             "Year",
             name,
             "time",
+            "entityColor",
         ])
 
         expect(table.get("3512").displayName).toBe("Some Display Name")
@@ -806,9 +839,10 @@ describe("creating a table from legacy", () => {
         const varSet = getOwidVarSet()
         varSet.get(3512)!.metadata.display!.conversionFactor = 100
         expect(
-            legacyToOwidTableAndDimensions(
+            legacyToOwidTableAndDimensionsWithMandatorySlug(
                 varSet,
-                getLegacyGrapherConfig().dimensions ?? []
+                getLegacyGrapherConfig().dimensions ?? [],
+                config.selectedEntityColors
             ).get("3512")!.values
         ).toEqual([550, 420, 1260])
     })
@@ -829,9 +863,10 @@ Papua New Guinea,PNG,1983,5.5`
     it("passes on the non-redistributable flag", () => {
         const varSet = getOwidVarSet()
         varSet.get(3512)!.metadata.nonRedistributable = true
-        const columnDef = legacyToOwidTableAndDimensions(
+        const columnDef = legacyToOwidTableAndDimensionsWithMandatorySlug(
             varSet,
-            getLegacyGrapherConfig().dimensions ?? []
+            getLegacyGrapherConfig().dimensions ?? [],
+            config.selectedEntityColors
         ).get("3512").def as OwidColumnDef
         expect(columnDef.nonRedistributable).toEqual(true)
     })
diff --git a/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.ts b/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.ts
index 79b4fa25e8..20836a136f 100644
--- a/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.ts
+++ b/packages/@ourworldindata/grapher/src/core/LegacyToOwidTable.ts
@@ -9,6 +9,8 @@ import {
     OwidVariableDimensions,
     OwidVariableDataMetadataDimensions,
     EntityId,
+    ErrorValue,
+    OwidChartDimensionInterfaceWithMandatorySlug,
 } from "@ourworldindata/types"
 import {
     OwidTable,
@@ -33,15 +35,18 @@ import {
     OwidVariableWithSourceAndDimension,
     ColumnSlug,
     EPOCH_DATE,
-    OwidChartDimensionInterface,
     OwidVariableType,
     memoize,
+    isEmpty,
 } from "@ourworldindata/utils"
 import { isContinentsVariableId } from "./GrapherConstants"
 
 export const legacyToOwidTableAndDimensions = (
     json: MultipleOwidVariableDataDimensionsMap,
-    dimensions: OwidChartDimensionInterface[]
+    dimensions: OwidChartDimensionInterfaceWithMandatorySlug[],
+    selectedEntityColors:
+        | { [entityName: string]: string | undefined }
+        | undefined
 ): OwidTable => {
     // Entity meta map
 
@@ -61,8 +66,7 @@ export const legacyToOwidTableAndDimensions = (
 
     // We need to create a column for each unique [variable, targetTime] pair. So there can be
     // multiple columns for a single variable.
-    const newDimensions = computeActualDimensions(dimensions)
-    const dimensionColumns = uniqBy(newDimensions, (dim) => dim.slug)
+    const dimensionColumns = uniqBy(dimensions, (dim) => dim.slug)
 
     const variableTablesToJoinByYear: OwidTable[] = []
     const variableTablesToJoinByDay: OwidTable[] = []
@@ -323,34 +327,36 @@ export const legacyToOwidTableAndDimensions = (
         }
     }
 
-    return joinedVariablesTable
-}
-
-export const addSelectedEntityColorsToTable = (
-    table: OwidTable,
-    selectedEntityColors: { [entityName: string]: string | undefined }
-): OwidTable => {
-    const entityColorColumnSlug = OwidTableSlugs.entityColor
-
-    const valueFn = (entityId: EntityId | undefined) => {
-        if (!entityId) return ErrorValueTypes.UndefinedButShouldBeString
-        const entityName = table.entityIdToNameMap.get(entityId)
-        return entityName && selectedEntityColors
-            ? (selectedEntityColors[entityName] ??
-                  ErrorValueTypes.UndefinedButShouldBeString)
-            : ErrorValueTypes.UndefinedButShouldBeString
-    }
+    // Append the entity color column if we have selected entity colors
+    if (!isEmpty(selectedEntityColors)) {
+        const entityColorColumnSlug = OwidTableSlugs.entityColor
+
+        const valueFn = (
+            entityId: EntityId | undefined
+        ): string | ErrorValue => {
+            if (!entityId) return ErrorValueTypes.UndefinedButShouldBeString
+            const entityName =
+                joinedVariablesTable.entityIdToNameMap.get(entityId)
+            return entityName && selectedEntityColors
+                ? (selectedEntityColors[entityName] ??
+                      ErrorValueTypes.UndefinedButShouldBeString)
+                : ErrorValueTypes.UndefinedButShouldBeString
+        }
 
-    const values = table.rows.map((row) => valueFn(row.entityId))
+        const values = joinedVariablesTable.rows.map((row) =>
+            valueFn(row.entityId)
+        )
 
-    return table.appendColumns([
-        {
-            slug: entityColorColumnSlug,
-            name: entityColorColumnSlug,
-            type: ColumnTypeNames.Color,
-            values: values,
-        },
-    ])
+        joinedVariablesTable = joinedVariablesTable.appendColumns([
+            {
+                slug: entityColorColumnSlug,
+                name: entityColorColumnSlug,
+                type: ColumnTypeNames.Color,
+                values: values,
+            },
+        ])
+    }
+    return joinedVariablesTable
 }
 
 const fullJoinTables = (
@@ -738,17 +744,6 @@ const annotationsToMap = (annotations: string): Map<string, string> => {
     return entityAnnotationsMap
 }
 
-export function computeActualDimensions(
-    dimensions: OwidChartDimensionInterface[]
-): OwidChartDimensionInterface[] {
-    return dimensions.map((dimension) => ({
-        ...dimension,
-        slug: dimension.targetYear
-            ? `${dimension.variableId}-${dimension.targetYear}`
-            : `${dimension.variableId}`,
-    }))
-}
-
 /**
  * Loads a single variable into an OwidTable.
  */
diff --git a/packages/@ourworldindata/types/src/OwidVariableDisplayConfigInterface.ts b/packages/@ourworldindata/types/src/OwidVariableDisplayConfigInterface.ts
index 6c7c0a182c..a4cdf8d60c 100644
--- a/packages/@ourworldindata/types/src/OwidVariableDisplayConfigInterface.ts
+++ b/packages/@ourworldindata/types/src/OwidVariableDisplayConfigInterface.ts
@@ -42,3 +42,8 @@ export interface OwidChartDimensionInterface {
     variableId: OwidVariableId
     slug?: ColumnSlug
 }
+
+export interface OwidChartDimensionInterfaceWithMandatorySlug
+    extends OwidChartDimensionInterface {
+    slug: ColumnSlug
+}
diff --git a/packages/@ourworldindata/types/src/index.ts b/packages/@ourworldindata/types/src/index.ts
index f5fd897166..0311df7b93 100644
--- a/packages/@ourworldindata/types/src/index.ts
+++ b/packages/@ourworldindata/types/src/index.ts
@@ -408,6 +408,7 @@ export {
     type OwidVariableDataTableConfigInterface,
     OwidVariableRoundingMode,
     type OwidChartDimensionInterface,
+    type OwidChartDimensionInterfaceWithMandatorySlug,
 } from "./OwidVariableDisplayConfigInterface.js"
 
 export {