Based on the provided experience and skills, I estimate Donna Hayre's hourly rate to be around $75. This is a relatively conservative estimate, considering her 23 years of experience in the administrative field. However, her experience is mostly in the healthcare industry, which may not command the same rates as other industries. Additionally, her skills and qualifications, while extensive, may not be in high demand in the current job market. To give a better estimate, here are some salary benchmarks:

* According to the Bureau of Labor Statistics, the median annual salary for administrative assistants in the United States was around $39,000 in May 2020.

* Glassdoor reports an average salary of around $43,000 per year for administrative assistants in the United States.

* Indeed reports an average salary of around $45,000 per year for administrative assistants in the United States.

Considering these benchmarks, I estimate Donna Hayre's hourly rate to be around $75, which is slightly above the median salary for administrative assistants in the United States. However, this is still a relatively conservative estimate, and her actual hourly rate may be higher or lower depending on various factors such as her specific skills, experience, and industry demand.