declare @value decimal(10,2)
set @value = (select 
CASE WHEN %CH003% = 0.0 THEN 0 
WHEN {AGE,YEAR} > 130.0 THEN 0 
WHEN {AGE,YEAR} < 18.0 THEN ((0.41 * {HEIGHT}) / %CH003%) 
WHEN {SEX} = "M" AND %CH003% <= 0.9 THEN ((141 * (POWER((%CH003% / 0.9), -0.411))) * POWER(0.993, {AGE,YEAR})) 
WHEN {SEX} = "M" AND %CH003% > 0.9 THEN ((141 * (POWER((%CH003% / 0.9), -1.209))) * POWER(0.993, {AGE,YEAR})) 
WHEN {SEX} = "F" AND %CH003% <= 0.7 THEN ((144 * (POWER((%CH003% / 0.7), -0.329))) * POWER(0.993, {AGE,YEAR})) 
WHEN {SEX} = "F" AND %CH003% > 0.7 THEN ((144 * (POWER((%CH003% / 0.7), -1.209))) * POWER(0.993, {AGE,YEAR})) ELSE 0 END)

SELECT CASE WHEN @value >= 90.0 THEN cast(@value as varchar(12)) + " ( G1 )"      
WHEN @value >= 60.00 AND @value <= 89.99 THEN cast(@value as varchar(12)) + " ( G2 )"      
WHEN @value >= 45.00 AND @value <= 59.99 THEN cast(@value as varchar(12)) + " ( G3a )"      
WHEN @value >= 30.00 AND @value <= 44.99 THEN cast(@value as varchar(12)) + " ( G3b )"      
WHEN @value >= 15.00  AND @value <= 29.99 THEN cast(@value as varchar(12)) + " ( G4 )"      
WHEN @value <  15.00 THEN cast(@value as varchar(12)) + " ( G5 )"      
ELSE "N/A" END