We do exactly what oomis1105 advised. Take 10% off the pay and deposit in another account to use for zedakah. This way there is no mistake about how much maaser you have to give. Maaser is maaser and has to be given even in difficult times. You can give more if possible but, never less than 10%. The seperate bank account helps you to know what you have always. Be matzliach, you should always have, to always give others.
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