proc sb:xptlvl { input } {
  global rs_exp
  set exp [string map {"," ""} $input]
  if {![sb:isnum $exp] || $exp == ""} { return "N/A" }
  for {set lvl 1} {$lvl <= 300} {incr lvl} {
    if {($exp >= [lindex $rs_exp $lvl]) && ($exp < [lindex $rs_exp [expr $lvl +1]])} { return "$lvl" }
  }
  return "N/A"
}