未声明的标识符错误＃C2065

我正在尝试构建一个具有多个函数和标识符的类。有问题的标识符是静态双AIR，它将保存班级中年利率的值。


我收到的错误信息似乎无法获得摆脱：


错误C2065：''AIR''未声明的标识符


我之前从未使用过静态标识符，我想我我在某个地方留下了什么，但我不知道是什么。


这里是标题和.cpp文件：


有什么想法吗？

I am trying to construct a class with several functions and identifiers. The identifier in question is static double AIR which will hold the value of the annual interest rate in the class.

I have been getting an error message that I can''t seem to get rid of:

error C2065: ''AIR'' undeclared identifier

I have never worked with static identifiers before and I think I''m leaving something out somewhere but I don''t know what.

Here''s the header and .cpp files:

Any Ideas?