A software engineering company has developed a coding scheme for efficient performance appraisal of its employees. It contains code YYYYSPEC-REMP, where, for an employee, YYYY represents the year of joining, SPEC represents work specialization, R represents the performance rating, and EMP represents the three-digit employee number.

a. What kind of code is used here? Describe the purpose behind each part of the code 1990PERT-A204.

b. Construct a coded entry using the same format and logic for an employee with the employee number 116, who joined the firm in 1983, received a B rating, and specializes in mainframe computers.

c. Construct a coded entry using the same format and logic for an employee who joined a few days back. Make your own assumptions. Discuss some possible limitations of this coding scheme in this scenario.