diff --git a/src/subsidy_base.h b/src/subsidy_base.h
--- a/src/subsidy_base.h
+++ b/src/subsidy_base.h
@@ -21,7 +21,7 @@ extern SubsidyPool _subsidy_pool;
 /** Struct about subsidies, offered and awarded */
 struct Subsidy : SubsidyPool::PoolItem<&_subsidy_pool> {
 	CargoID cargo_type;  ///< Cargo type involved in this subsidy, CT_INVALID for invalid subsidy
-	byte remaining;      ///< Remaining months when this subsidy is valid
+	uint16 remaining;    ///< Remaining months when this subsidy is valid
 	CompanyID awarded;   ///< Subsidy is awarded to this company; INVALID_COMPANY if it's not awarded to anyone
 	SourceType src_type; ///< Source of subsidised path (ST_INDUSTRY or ST_TOWN)
 	SourceType dst_type; ///< Destination of subsidised path (ST_INDUSTRY or ST_TOWN)
@@ -52,11 +52,18 @@ struct Subsidy : SubsidyPool::PoolItem<&
 
 /** Constants related to subsidies */
 static const uint SUBSIDY_OFFER_MONTHS         =  12; ///< Duration of subsidy offer
-static const uint SUBSIDY_CONTRACT_MONTHS      =  12; ///< Duration of subsidy after awarding
 static const uint SUBSIDY_PAX_MIN_POPULATION   = 400; ///< Min. population of towns for subsidised pax route
 static const uint SUBSIDY_CARGO_MIN_POPULATION = 900; ///< Min. population of destination town for cargo route
 static const uint SUBSIDY_MAX_PCT_TRANSPORTED  =  42; ///< Subsidy will be created only for towns/industries with less % transported
 static const uint SUBSIDY_MAX_DISTANCE         =  70; ///< Max. length of subsidised route (DistanceManhattan)
 static const uint SUBSIDY_TOWN_CARGO_RADIUS    =   6; ///< Extent of a tile area around town center when scanning for town cargo acceptance and production (6 ~= min catchmement + min station / 2)
 
+/** Types of subsidy news messages, which determine how the date is printed and whether to use singular or plural cargo names */
+enum class SubsidyDecodeParamType {
+	NewsOffered   = 0, ///< News item for an offered subsidy
+	NewsAwarded   = 1, ///< News item for an awarded subsidy
+	NewsWithdrawn = 2, ///< News item for a subsidy offer withdrawn, or expired subsidy
+	Gui           = 3, ///< Subsidies listed in the Subsidy GUI
+};
+
 #endif /* SUBSIDY_BASE_H */