diff --git a/src/newgrf_spritegroup.cpp b/src/newgrf_spritegroup.cpp
--- a/src/newgrf_spritegroup.cpp
+++ b/src/newgrf_spritegroup.cpp
@@ -84,7 +84,7 @@ static inline uint32 GetVariable(const R
 	/* Return common variables */
 	switch (variable) {
 		case 0x00: return max(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0);
-		case 0x01: return clamp(_cur_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR;
+		case 0x01: return Clamp(_cur_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR;
 		case 0x02: return _cur_month;
 		case 0x03: return _opt.landscape;
 		case 0x09: return _date_fract;