diff --git a/src/newgrf_industries.cpp b/src/newgrf_industries.cpp
--- a/src/newgrf_industries.cpp
+++ b/src/newgrf_industries.cpp
@@ -396,16 +396,16 @@ static uint32_t GetCountAndDistanceOfClo
 		case 0xA6: return indspec->grf_prop.local_id;
 		case 0xA7: return this->industry->founder;
 		case 0xA8: return this->industry->random_colour;
-		case 0xA9: return ClampTo<uint8_t>(this->industry->last_prod_year - ORIGINAL_BASE_YEAR);
+		case 0xA9: return ClampTo<uint8_t>(this->industry->last_prod_year - CalendarTime::ORIGINAL_BASE_YEAR);
 		case 0xAA: return this->industry->counter;
 		case 0xAB: return GB(this->industry->counter, 8, 8);
 		case 0xAC: return this->industry->was_cargo_delivered;
 
-		case 0xB0: return ClampTo<uint16_t>(this->industry->construction_date - DAYS_TILL_ORIGINAL_BASE_YEAR); // Date when built since 1920 (in days)
+		case 0xB0: return ClampTo<uint16_t>(this->industry->construction_date - CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR); // Date when built since 1920 (in days)
 		case 0xB3: return this->industry->construction_type; // Construction type
 		case 0xB4: {
 			auto it = std::max_element(std::begin(this->industry->accepted), std::end(this->industry->accepted), [](const auto &a, const auto &b) { return a.last_accepted < b.last_accepted; });
-			return ClampTo<uint16_t>(it->last_accepted - DAYS_TILL_ORIGINAL_BASE_YEAR); // Date last cargo accepted since 1920 (in days)
+			return ClampTo<uint16_t>(it->last_accepted - CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR); // Date last cargo accepted since 1920 (in days)
 		}
 	}