If it went up 1500% again, it would add 45% to R2K.
Though the point is that any one stock that goes up by 200% (from $1 to $3) can replace 4 stocks that drop by 50% (each dropping from $1 to $0.50), or 8 stocks that drop by 25%. This is with small/equal weighing.
When a few companies get killed, the business is usually taken over by another one. Similarly with investors' money - they can move from several stocks into one, even without fundamentals.
