Teacher:Based on the information present in the given passage, you need to write a correct answer to the given question. A correct answer is one that correctly and completely answers the question. Do not write answers that address the question partially or incorrectly. The correct answer must be contained in the given paragraph.
Teacher: Now, understand the problem? Solve this instance: Paragraph- Sent 1: Her career started more than 20 years ago in a garage behind a Catholic Worker soup kitchen on skid row in Los Angeles.
Sent 2: She lived on a $3-a-week stipend that she spent on pantyhose and bus fare.
Sent 3: Her law practice grew to an organization that brought in millions of dollars of damages through its cases against L.A. slumlords, allowing poor families to set up college funds and buy homes.
Sent 4: In all those years, she never lost a case.
Sent 5: When she stepped down, she had time to notice what was happening to the field of poverty law.
Sent 6: "I realized with a shock that the work had really disintegrated and we had lost a whole generation of public-interest lawyers," she said.
Sent 7: "It had gone from being an economic sacrifice as it was in my day to an economic impossibility.
Sent 8: ... The whole system has essentially collapsed."Sent 9: Mintie also started to ask questions about the medical field.
Sent 10: Almost every person who walks into a free medical clinic, she said, faces some legal problem such as an eviction or the loss of Social Security benefits.
Sent 11: And many of her clients had medical problems from living in slum housing such as cockroaches lodged in ear canals and rat bite fever, a nonfatal malady that particularly affects children.
Sent 12: Mintie noticed that health-care professionals were graduating with staggering debts and also couldn't afford to work with the poor.
Sent 13: Her work was noticed by Oprah Winfrey, who invited her on the TV show March 26, 2001.
Sent 14: Mintie received a $100,000 "Use Your Life Award" from Oprah's Angel Network, a nonprofit organization that awards money to those who help others.
Sent 15: Mintie said that all of the money has gone to her recipients -- none was spent on overhead.
Sent 16: She will be out of funds by spring.
Sent 17: She is trying to get religious organizations to sponsor recipients.
Sent 18: It is a secular organization, but one that grew out of Mintie's religious convictions. 
Question: How many years did Mintie go without losing a case?.
Student:
20 years.