In my first job in advertising telesales, we were encouraged to use the following phrase to get around the old "I have no money" objection:

"When business is good, it pays to advertise; when it's not so good, you need to advertise." 

Sure, it was cheesy as hell but to a degree the principle still holds true. However, trying to convince the company board that you need to spend more - or at the very least the same - when revenues are dropping is challenging in the extreme.

As a result, getting your attribution model and process in shape is more critical than ever, as it allows a clear demonstration of ROI across the marketing function and the strategy / tactics you've employed. 

After all, those dropping revenues may be nothing to do with marketing and everything to do with those cheesy sales people.