Yenlong
SPX vs. NIKKEI225 SELL; Massive SHORT!!SHORT this spread endlessly!!
Here is the Weekly
The "math" bears this out, readily! NIKKEI225 has a 13%-15% advantage - including FX - over the SPX. This is by far the best Equities/Risk spread out there if one must be long equities. (... which one ought Not to want to do under any circumstance, at these levels! :-)
Here is the FX component - USDJPY