From a report by JLL: The 3-30-300 rule
There is a “3-30-300” rule of thumb that organizations typically spend approximately $3 per square foot per year for utilities, $30 for rent and $300 for payroll. While these figures are just archetypes, they are useful in providing an order of magnitude between the three areas of expenditure. According to the 3-30-300 model, the greatest financial savings from greening a workplace may not be in energy but in productivity. A 2% energy efficiency improvement would result in savings of $.06 per square foot but a 2% improvement in productivity would result in $6 per square foot through increased employee performance. As beneficial as energy savings can be, any green investment that increases employee wellness and productivity can have exponentially greater value.
3. Botanic Art
Nature restores mental functioning in the same way that food and water restore bodies. The business of everyday life — dodging traffic, making decisions and judgment calls, interacting with strangers, answering emails — is depleting, and what man-made environments take away from us, nature gives back. There’s something mystical and, you might say, unscientific about this claim, but its heart actually rests in what psychologists call attention restoration theory (ART). According to ART, urban environments are draining because they force us to direct our attention to specific tasks (e.g., avoiding the onslaught of traffic) and grab our attention dynamically, compelling us to “look here!” before telling us to instead “look over there!” These demands are draining — and they’re also absent in natural environments. Forests, streams, rivers, lakes, and oceans demand very little from us, though they’re still engaging, ever changing, and attention-grabbing. The difference between natural and urban landscapes is how they command our attention. While man-made landscapes bombard us with stimulation, their natural counterparts give us the chance to think as much or as little as we’d like, and the opportunity to replenish exhausted mental resources.
From an Article in the Atlantic in 2013 entitled How Nature Resets Our Minds and Bodies