data_strings = ["10.0", "20.0", "30.0", "40.0", "50.0"]
data_floats = []
number_of_values = 5

for i in range(1,number_of_values):
    print("loop start") 
    print("i - 1 = ", i - 1)
    string_value = data_strings[i - 1]     
    print(string_value)     
    float_value = float(string_value)     
    print(float_value)     
    data_floats.append(float_value) 
    print("loop end") 

    
print(sum(data_floats))