Difficulty in pow function for ZScore calculation

Hello Community and Experts
I compiled a form for surveillance of cases of stunting and malnutrition under five. in the form there is 1 question that will be able to process the Zscore calculation if questions related to weight and height are filled in. In summary, the form in my design is attached below with a simplified table reference (just as an example) which is used for the Lookup function or the Pulldata function. The calculation approach used is the LMS method (LMS Table). I am trying to design an xls form and there are difficulties related to the preparation of the calculation formula. especially the syntax for exponential on variables in step 2 how to write an exponential function with powers corresponding to the values in “L”, pow(${step1}, {l_tb}) There is an error, please help with the solution, thank you.
Form LMS V1.0 (2).xlsx (6.3 KB)
LMS_table.csv (330 Bytes)

@dedik2urniawan, when you pull data the values are stored in text format. To make calculations you will need to transform the text to integers as outlined in the post discussed previously:

Thanks @Kal_Lam , this works. it turns out that I tried to add the Int(Q) syntax the result actually shows a number (integer type), while the expected result is decimal. after I checked it turned out that the syntax in step 2 (according to the flow in the xls form) I didn’t add “$” to the function in “Pow” pow(${step1}, ${l_tb}). thank you @Kal_Lam finally make a ZScore calculation (LMS Methods) for growth assessment can work in Kobotoolbox.