diff --git a/src/misc.cpp b/src/misc.cpp
index 5a37299fe8..daf70b130a 100644
--- a/src/misc.cpp
+++ b/src/misc.cpp
@@ -101,6 +101,7 @@ void InitializeGame(uint size_x, uint size_y, bool reset_date, bool reset_settin
 	_game_speed = 100;
 	citymania::_pause_countdown = 0;
 	TimerGameTick::counter = 0;
+	TimerGameEconomy::days_since_last_month = 0;
 	_cur_tileloop_tile = TileIndex{1};
 	_thd.redsq = INVALID_TILE;
 	if (reset_settings) MakeNewgameSettingsLive();
diff --git a/src/saveload/misc_sl.cpp b/src/saveload/misc_sl.cpp
index b39fd67eaa..abd29aac90 100644
--- a/src/saveload/misc_sl.cpp
+++ b/src/saveload/misc_sl.cpp
@@ -87,6 +87,7 @@ static const SaveLoad _date_desc[] = {
 	SLEG_CONDVAR("tick_counter",           TimerGameTick::counter,           SLE_UINT64,                  SLV_U64_TICK_COUNTER, SL_MAX_VERSION),
 	SLEG_CONDVAR("economy_date",           TimerGameEconomy::date,           SLE_INT32,                   SLV_ECONOMY_DATE, SL_MAX_VERSION),
 	SLEG_CONDVAR("economy_date_fract",     TimerGameEconomy::date_fract,     SLE_UINT16,                  SLV_ECONOMY_DATE, SL_MAX_VERSION),
+	SLEG_CONDVAR("days_since_last_month",  TimerGameEconomy::days_since_last_month, SLE_UINT32,           SLV_INDUSTRY_ACCEPTED_HISTORY, SL_MAX_VERSION),
 	SLEG_CONDVAR("calendar_sub_date_fract", TimerGameCalendar::sub_date_fract, SLE_UINT16,                SLV_CALENDAR_SUB_DATE_FRACT, SL_MAX_VERSION),
 	SLEG_CONDVAR("age_cargo_skip_counter", _age_cargo_skip_counter, SLE_UINT8,                   SL_MIN_VERSION, SLV_162),
 	SLEG_CONDVAR("cur_tileloop_tile",      _cur_tileloop_tile,      SLE_FILE_U16 | SLE_VAR_U32,  SL_MIN_VERSION, SLV_6),