Discounts | WordPress.org

Hi,

I have an online shop with arround 600 artcles and many variations. When I like to give discounts I manually have to give in the price and period for every variation of an article which is a lot of work to do. I wonder if there is a plugin to easaly do that without giving in the price and period for every variation.

Thank you

The page I need help with: [log in to see the link]