<prompt> Translate the following text to EnglishKwa mfano, kwa mfano, katika miaka ya 1990 na 1997, barua za biashara za NHH-to-NHH zilikuwa na ukuaji mzuri wa kiasi.  <response>: Now let us evaluate the historical volume data in Table 1. In the 90s 1990-97, only NHH-to-NHH business mail has experienced healthy volume growth. 