This charts are last year's sales figures for the appliance and electronics megastore. How can I explain this charts to the store manager seasonal variations in each department? Thank you

Month January February March April May June July August September October November December Home Electronics Computers Appliances 68 39 72 34 75 41 54 41 56 42 49 33 54 31 66 58 62 58 66 44 83 48 91 62 36 34 30 28 44 48 43 39 36 33 29 24 Sales in 2006 (in $ thousands) Home Electronics Computers Appliances 91 83 68 72 75 66 66 6258 52 54 141 56 14244 49 48 48 3936 3434 41 30 43 31 39 36 44 33 28 24 April July May June October September March August January November December February