¥160 ⅌ $1 seems to be the limit for the BOJ. When they intervene, it goes down to ¥152 or ¥156, depending on their spend.
But no one knows if it would become much worse than ¥160 because they never let it go beyond that. I say “levels off” at ¥160 because... here’s the last six months. Could it go beyond ¥160? Sure. By a lot? We’ll never know. But the trajectory doesn’t indicate it would.