Today's tape split SNSUC's thirteen categories in two. On the heavy side, fuel oil at ¥5,424/t (+2.24%) and bitumen at ¥5,096/t (+3.05%) pushed up together — refinery turnaround season plus bunker demand held the crack.

The rubber side moved the other way: natural rubber at ¥19,140/t (-2.17%) led the slide while butadiene rubber at ¥16,750/t (+0.15%) barely moved, as upstream butadiene gave ground but tire makers bought only to need.

The split sets the trade play plainly: the heavy chain can lock the near month and bet on turnarounds lasting; the rubber chain favors basis trades over direction. We now quote clients on two separate formulas — a heavy group and a rubber group — so one curve's move can't misread the other book.