How many sign language interpreters are there who, like Callis, specialize in sign language interpreting?

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For spoken language interpreting, interpreters often join ATA as well as specialized associations, such as the National Association of Judiciary Interpreters and Translators for court interpreting, and the International Medical Interpreters Association for healthcare interpreting.

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Currently, there is a national shortage of sign language interpreters in the United States, even though there are 40 schools offering bachelor degree programs in American Sign Language (ASL) interpreting and 78 that offer associate degrees.

FORBES: Lydia Callis and the Biggest Industry You've Never Heard Of