Backfill land parameters for 2021 to 2023

Author: MaxGhenis

policyengine_uk/parameters/household/wealth/land/value.yaml

@@ -8,6 +8,9 @@ aggregate_household_land_value:
     2018-01-01: 3_947_306_000_000
     2019-01-01: 3_961_152_000_000
     2020-01-01: 4_309_138_000_000
+    2021-01-01: 5_047_690_687_279
+    2022-01-01: 5_070_355_908_968
+    2023-01-01: 4_798_764_603_941
     2024-01-01: 5_041_350_906_096
     2025-01-01: 5_041_350_906_096
     2026-01-01: 5_041_350_906_096
@@ -28,6 +31,9 @@ aggregate_corporate_land_value:
     2018-01-01: 1_695_825_000_000
     2019-01-01: 1_683_117_000_000
     2020-01-01: 1_757_818_000_000
+    2021-01-01: 2_059_094_312_721
+    2022-01-01: 2_068_340_091_032
+    2023-01-01: 1_957_550_396_059
     2024-01-01: 2_058_649_093_904
     2025-01-01: 2_058_649_093_904
     2026-01-01: 2_058_649_093_904