diff --git a/src/script/api/script_company.cpp b/src/script/api/script_company.cpp
index b35234f5a7..9024dc8ee9 100644
--- a/src/script/api/script_company.cpp
+++ b/src/script/api/script_company.cpp
@@ -114,11 +114,12 @@
 	return HasBit(ge, ::GENDER_FEMALE) ? GENDER_FEMALE : GENDER_MALE;
 }
 
-/* static */ Money ScriptCompany::GetQuarterlyIncome(ScriptCompany::CompanyID company, uint32 quarter)
+/* static */ Money ScriptCompany::GetQuarterlyIncome(ScriptCompany::CompanyID company, SQInteger quarter)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return -1;
 	if (quarter > EARLIEST_QUARTER) return -1;
+	if (quarter < CURRENT_QUARTER) return -1;
 
 	if (quarter == CURRENT_QUARTER) {
 		return ::Company::Get(company)->cur_economy.income;
@@ -126,11 +127,12 @@
 	return ::Company::Get(company)->old_economy[quarter - 1].income;
 }
 
-/* static */ Money ScriptCompany::GetQuarterlyExpenses(ScriptCompany::CompanyID company, uint32 quarter)
+/* static */ Money ScriptCompany::GetQuarterlyExpenses(ScriptCompany::CompanyID company, SQInteger quarter)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return -1;
 	if (quarter > EARLIEST_QUARTER) return -1;
+	if (quarter < CURRENT_QUARTER) return -1;
 
 	if (quarter == CURRENT_QUARTER) {
 		return ::Company::Get(company)->cur_economy.expenses;
@@ -138,11 +140,12 @@
 	return ::Company::Get(company)->old_economy[quarter - 1].expenses;
 }
 
-/* static */ int32 ScriptCompany::GetQuarterlyCargoDelivered(ScriptCompany::CompanyID company, uint32 quarter)
+/* static */ SQInteger ScriptCompany::GetQuarterlyCargoDelivered(ScriptCompany::CompanyID company, SQInteger quarter)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return -1;
 	if (quarter > EARLIEST_QUARTER) return -1;
+	if (quarter < CURRENT_QUARTER) return -1;
 
 	if (quarter == CURRENT_QUARTER) {
 		return ::Company::Get(company)->cur_economy.delivered_cargo.GetSum<OverflowSafeInt32>();
@@ -150,21 +153,22 @@
 	return ::Company::Get(company)->old_economy[quarter - 1].delivered_cargo.GetSum<OverflowSafeInt32>();
 }
 
-/* static */ int32 ScriptCompany::GetQuarterlyPerformanceRating(ScriptCompany::CompanyID company, uint32 quarter)
+/* static */ SQInteger ScriptCompany::GetQuarterlyPerformanceRating(ScriptCompany::CompanyID company, SQInteger quarter)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return -1;
 	if (quarter > EARLIEST_QUARTER) return -1;
-	if (quarter == CURRENT_QUARTER) return -1;
+	if (quarter <= CURRENT_QUARTER) return -1;
 
 	return ::Company::Get(company)->old_economy[quarter - 1].performance_history;
 }
 
-/* static */ Money ScriptCompany::GetQuarterlyCompanyValue(ScriptCompany::CompanyID company, uint32 quarter)
+/* static */ Money ScriptCompany::GetQuarterlyCompanyValue(ScriptCompany::CompanyID company, SQInteger quarter)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return -1;
 	if (quarter > EARLIEST_QUARTER) return -1;
+	if (quarter < CURRENT_QUARTER) return -1;
 
 	if (quarter == CURRENT_QUARTER) {
 		return ::CalculateCompanyValue(::Company::Get(company));
@@ -278,12 +282,13 @@
 	return ::Company::Get(company)->settings.engine_renew;
 }
 
-/* static */ bool ScriptCompany::SetAutoRenewMonths(int16 months)
+/* static */ bool ScriptCompany::SetAutoRenewMonths(SQInteger months)
 {
+	months = Clamp<SQInteger>(months, INT16_MIN, INT16_MAX);
 	return ScriptObject::Command<CMD_CHANGE_COMPANY_SETTING>::Do("company.engine_renew_months", months);
 }
 
-/* static */ int16 ScriptCompany::GetAutoRenewMonths(CompanyID company)
+/* static */ SQInteger ScriptCompany::GetAutoRenewMonths(CompanyID company)
 {
 	company = ResolveCompanyID(company);
 	if (company == COMPANY_INVALID) return 0;
diff --git a/src/script/api/script_company.hpp b/src/script/api/script_company.hpp
index 4fc496d967..ad82b88b6a 100644
--- a/src/script/api/script_company.hpp
+++ b/src/script/api/script_company.hpp
@@ -263,7 +263,7 @@ public:
 	 * @pre quarter <= EARLIEST_QUARTER.
 	 * @return The gross income of the company in the given quarter.
 	 */
-	static Money GetQuarterlyIncome(CompanyID company, uint32 quarter);
+	static Money GetQuarterlyIncome(CompanyID company, SQInteger quarter);
 
 	/**
 	 * Get the expenses of the company in the given quarter.
@@ -276,7 +276,7 @@ public:
 	 * @pre quarter <= EARLIEST_QUARTER.
 	 * @return The expenses of the company in the given quarter.
 	 */
-	static Money GetQuarterlyExpenses(CompanyID company, uint32 quarter);
+	static Money GetQuarterlyExpenses(CompanyID company, SQInteger quarter);
 
 	/**
 	 * Get the amount of cargo delivered by the given company in the given quarter.
@@ -286,7 +286,7 @@ public:
 	 * @pre quarter <= EARLIEST_QUARTER.
 	 * @return The amount of cargo delivered by the given company in the given quarter.
 	 */
-	static int32 GetQuarterlyCargoDelivered(CompanyID company, uint32 quarter);
+	static SQInteger GetQuarterlyCargoDelivered(CompanyID company, SQInteger quarter);
 
 	/**
 	 * Get the performance rating of the given company in the given quarter.
@@ -298,7 +298,7 @@ public:
 	 * @note The performance rating is calculated after every quarter, so the value for CURRENT_QUARTER is undefined.
 	 * @return The performance rating of the given company in the given quarter.
 	 */
-	static int32 GetQuarterlyPerformanceRating(CompanyID company, uint32 quarter);
+	static SQInteger GetQuarterlyPerformanceRating(CompanyID company, SQInteger quarter);
 
 	/**
 	 * Get the value of the company in the given quarter.
@@ -308,7 +308,7 @@ public:
 	 * @pre quarter <= EARLIEST_QUARTER.
 	 * @return The value of the company in the given quarter.
 	 */
-	static Money GetQuarterlyCompanyValue(CompanyID company, uint32 quarter);
+	static Money GetQuarterlyCompanyValue(CompanyID company, SQInteger quarter);
 
 	/**
 	 * Build your company's HQ on the given tile.
@@ -351,10 +351,11 @@ public:
 	/**
 	 * Set the number of months before/after max age to autorenew an engine for your company.
 	 * @param months The new months between autorenew.
+	 *               The value will be clamped to MIN(int16) .. MAX(int16).
 	 * @return True if autorenew months has been modified.
 	 * @api -game
 	 */
-	static bool SetAutoRenewMonths(int16 months);
+	static bool SetAutoRenewMonths(SQInteger months);
 
 	/**
 	 * Return the number of months before/after max age to autorenew an engine for a company.
@@ -362,7 +363,7 @@ public:
 	 * @pre ResolveCompanyID(company) != COMPANY_INVALID.
 	 * @return The months before/after max age of engine.
 	 */
-	static int16 GetAutoRenewMonths(CompanyID company);
+	static SQInteger GetAutoRenewMonths(CompanyID company);
 
 	/**
 	 * Set the minimum money needed to autorenew an engine for your company.