Be on the skids
Definition 1 of 1
Pro Tip 1/3Negative Connotation
The phrase often implies a sense of disappointment or concern about the decline. 
After losing several games, the team is on the skids, worrying the fans.
Pro Tip 2/3Not Literal
'On the skids' doesn't mean a physical slide, but a metaphorical descent. 
The singer's career is on the skids since his last album flopped.
Pro Tip 3/3Informal Usage
Use the phrase in casual conversations rather than formal writing or speech. 
Since the new policy, morale at work is on the skids.