Formula Understanding

Hi there,

Please can someone verify if whether my understanding of the following formula is correct, it's showing the % difference between current and previous data:

FORMULA:

=IFERROR((IFERROR(VLOOKUP($A7,'Current'!$A$3:$CZ$68,MATCH(J$6,'Current'!$A$3:$CZ$3,0),FALSE),0)-IFERROR(VLOOKUP($A7,'Previous'!$A$3:$CZ$54, MATCH (J$6,'Previous'!$A$3:$CZ$3,0), FALSE),0))/(IF(IFERROR(VLOOKUP($A7,’Current'!$A$3:$CZ$68,MATCH(J$6,’Current'!$A$3:$CZ$3,0),FALSE),0)=0, IFERROR(VLOOKUP($A7,'Previous'!$A$3:$CZ$54, MATCH(J$6,’Previous'!$A$3:$CZ$3,0),FALSE),0),IFERROR(VLOOKUP($A7,'Current’!$A$3:$CZ$68,MATCH(J$6,'Current'!$A$3:$CZ$3,0),FALSE),0))),0)

INTERPRETATION:

Take the Current, minus the Previous. IFERROR within either return the Current of Previous return a 0. Take the result, divide it by Current. IFERROR shows for either Previous or Current, return a 0.

Thank you!