In the 1970s and early 1980s, the cost of making a phone call decreased and more business communication was done by phone. As corporations grew and labor rates increased, the ratio of secretaries to employees decreased. With multiple time zones, fewer secretaries and more communication by phone, real-time phone communications were hampered by callers being unable to reach people. Some early studies showed that only 1 in 4 phone calls resulted in a completed call and half the calls were one-way in nature (that is, they did not require a conversation). This happened because people were either not at work (due to time zone differences, being away on business, etc.), or if they were at work, they were on the phone, away from their desks in meetings, on breaks, etc. This bottleneck hindered the effectiveness of business activities and decreased both individual and group productivity. It also wasted the caller’s time and created delays in resolving time-critical issues.