1633
The breach may be the most extensive since 2015 , when thieves gained access to the tax returns of over 300,000 people by using stolen data and filed fraudulent returns to get refunds .
 thieves: attacker; get refunds: purpose; people: victim; 300,000: number of victim; using stolen data and filed fraudulent returns: attack pattern
Given event type and trigger, please tell me the arguments of all the listed option. Output format is "name1: role1; name2: role2". 
Event type: data breach 
  Option: victim, attacker, attack pattern, purpose, damage amount, tool, time, place, number of victim, compromised data, number of data 
Text: {0} 
Answer:
 thieves: attacker; get refunds: purpose; people: victim; 300,000: number of victim; using stolen data and filed fraudulent returns: attack pattern