Final answer:
The given information does not provide the total number of outstanding shares for Concord Corporation at December 31, 2023.
Step-by-step explanation:
The question you are asking about Concord Corporation's total number of outstanding shares at December 31, 2023 is not provided in the given information. The information you provided is about Darkroom Windowshade Company, which has 100,000 shares of stock outstanding. It does not provide information about Concord Corporation's shares. Therefore, it is not possible to determine the answer to your question based on the given information.