The invention relates to a bound phosphorus-modified catalyst composition comprising a zeolite having a silica to alumina molar ratio of at least 40 and a binder having a surface area less than 200 m /g, wherein the bound catalyst composition exhibits a mesopore size distribution with less than 20% of mesopores having a size below 10 nm before steaming in approximately 100% steam for about 96 hours at about 1000 DEG F (about 538 DEG C) and with more than 60% of mesopores having a size at least 21 nm after steaming in approximately 100% steam for about 96 hours at about 1000 DEG F (about 538 DEG C).