A system comprising: at least one domain, wherein the at least one domain includes one or more processors and a memory; wherein the at least one domain includes at least one module that is configured to: obtain at least one event including the at least one personal identifier; compute a first obfuscated value for the at least one personal identifier; maintain a delete table, the delete table including a plurality of entries for deleted personal identifiers, an entry including a first obfuscated value and a second obfuscated value, the first obfuscated value associated with a first-generation randomized value, the second obfuscated value based on a current-generation randomized value; search for the first obfuscated value in the delete table; when the first obfuscated value is not found in the delete table, store the at least one personal identifier and the first obfuscated value in a reversible map that maps the obfuscated value to at least one personal identifier, and replace the at least one personal identifier with the first obfuscated value in the at least one event; when the first obfuscated value is found in the delete table, obtain the second obfuscated value from the delete table, and replace the at least one personal identifier with the second obfuscated value in the at least one event; and utilize the event data without reference to the at least one personal identifier. at least one domain, wherein the at least one domain includes one or more processors and a memory; wherein the at least one domain includes at least one module that is configured to: obtain at least one event including the at least one personal identifier; compute a first obfuscated value for the at least one personal identifier; maintain a delete table, the delete table including a plurality of entries for deleted personal identifiers, an entry including a first obfuscated value and a second obfuscated value, the first obfuscated value associated with a first-generation randomized value, the second obfuscated value based on a current-generation randomized value; search for the first obfuscated value in the delete table; when the first obfuscated value is not found in the delete table, store the at least one personal identifier and the first obfuscated value in a reversible map that maps the obfuscated value to at least one personal identifier, and replace the at least one personal identifier with the first obfuscated value in the at least one event; when the first obfuscated value is found in the delete table, obtain the second obfuscated value from the delete table, and replace the at least one personal identifier with the second obfuscated value in the at least one event; and utilize the event data without reference to the at least one personal identifier. obtain at least one event including the at least one personal identifier; compute a first obfuscated value for the at least one personal identifier; maintain a delete table, the delete table including a plurality of entries for deleted personal identifiers, an entry including a first obfuscated value and a second obfuscated value, the first obfuscated value associated with a first-generation randomized value, the second obfuscated value based on a current-generation randomized value; search for the first obfuscated value in the delete table; when the first obfuscated value is not found in the delete table, store the at least one personal identifier and the first obfuscated value in a reversible map that maps the obfuscated value to at least one personal identifier, and replace the at least one personal identifier with the first obfuscated value in the at least one event; when the first obfuscated value is found in the delete table, obtain the second obfuscated value from the delete table, and replace the at least one personal identifier with the second obfuscated value in the at least one event; and utilize the event data without reference to the at least one personal identifier. <EOS>