Indecline?

Last week I walked down to the local train station and discovered this bit of street art. So whoever stencilled it cannot spell but apart from that I find it rather odd and quaint.

That day signalled the weather that was to come, reaching 44 degrees celsius later that week. I wonder if anyone else in my area has noticed the "indecline" and ponders the meaning behind it.

I feel as though a question mark should be added to the word, or to even ask "are we in decline?"

Today is another beaut day, perfect for another walk to the station.