# Error in DOMO documentation - POP: QTD Quarter-over-Quarter Comparison

Hi,

I was trying to use Beast Mode that is provided here: https://domohelp.domo.com/hc/en-us/articles/360043430133-Sample-Beast-Mode-Calculations-Period-over-Period-Transforms#7.2., however the formula is not valid for Multiple Series - Previous Period. The error comes from additional ")" bracket that doesn't have corresponding opening bracket. If I remove the ")", the formula is valid, but the numbers are all wrong. I tried to place the opening "(" in few different places, but with no success.

• Have you tried breaking this down and start with a table card and then create a beast mode for each of the functions and see what they return in the table card and then building it up from there? That should reveal where the error in the calculation is.

You might also want to look at a nice write-up @GrantSmith did on a flexible way to do period over period comparisons. https://dojo.domo.com/discussion/53481/a-more-flexible-way-to-do-period-over-period-comparisons#latest

**Make sure to any users posts that helped you.
• For anyone facing this problem, here's a solution. My colleague fixed and simplified the formula:

CASE

When

(

-- Check Date is in previous quarter

CASE

When QUARTER(CURDATE()) = 1 and (QUARTER(`Datefield`) = 4 and (YEAR(`Datefield`) = YEAR(CURDATE())-1))

or

((QUARTER(CURDATE())-1 = QUARTER(`Datefield`)) and (YEAR(`Datefield`) = YEAR(CURDATE()))) then 'T'

END

) = 'T'

AND

-- check days in Q are equal

-- days in CQ

(

-- Days from start of quarter to Current date

DATEDIFF( CURDATE(),

CASE

When QUARTER(CURDATE()) = 1 then CONCAT(YEAR(CURDATE()), '-01-01')

When QUARTER(CURDATE()) = 2 then CONCAT(YEAR(CURDATE()), '-04-01')

When QUARTER(CURDATE()) = 3 then CONCAT(YEAR(CURDATE()), '-07-01')

When QUARTER(CURDATE()) = 4 then CONCAT(YEAR(CURDATE()), '-10-01')

END

)

) -- current Q days is >= Date Q days

>=

-- get Date Q days

-- Days from start of Date field quarter to date

(

DATEDIFF( `Datefield`,

CASE

When QUARTER(`Datefield`) = 1 then CONCAT(YEAR(`Datefield`), '-01-01')

When QUARTER(`Datefield`) = 2 then CONCAT(YEAR(`Datefield`), '-04-01')

When QUARTER(`Datefield`) = 3 then CONCAT(YEAR(`Datefield`), '-07-01')

When QUARTER(`Datefield`) = 4 then CONCAT(YEAR(`Datefield`), '-10-01')

END

)

)

then `Amountfield`

END