Declining advertising sales have been a big issue but my sales have dropped as well and that should not be happening.
You should first check on what is making the company to be draged behind
if cant solve then you should look for a people with successful business for a long period without making no losses gate advises from them like companies communication companies, Internet companies and many of the successful
Then if you are the director of the company you should have closeness to your employees so that hou can notice early enough before the company drops down.