Why is my data usage so high?

Question

Using Verizon's data calculator, 5G should me more than sufficient for the limited PC usage.  In one week, the data usage information indicates we have used over half in one week.  There are several entries in the breakdown for small amounts during the midnight hours, when computers are not in use and shut down. 
I am very disappointed with the information provided before this plan was purchased, based on what we expected for our data needs.  By increasing the data amount our bill will increase 30.00  There are many sources that indicate 2G should be ample for each of us in the household (2).  So, I am not sure the calculations are correct that are being tracked with the Jetpack system.  Here is the data calculator, I entered more than twice the expected usage for the two laptops combined.  We download no music, videos, movies.  Simply check email and browse the web.  How do you explain this?
Total
3 GB/mo
(3157 MB/mo)
Mobile
Broadband
4G
3 GB/mo
5/21/2014 Data Calculator - Verizon Wireless

Answer 1

The VZW Data Calculator is a tool designed to help estimate and visualize data usage.  Most folks have no idea what data is or how it is consumed on their devices.  The data calculator tool is not accurate on any front other than to give you a general idea how much data a particular function consumes under normal circumstances.
VZW provides its users with a limited data usage report that does not break down individual application or device usage into meaningful results.  What you get instead is a power bill like summary of your usage in terms of how much was used at certain times of the day.  After all VZW is not in the computer support business, they provide you with the pipe and users determine how best to consume the data.  A leaky hose or application is not the responsibility of VZW to discover and correct.
When it comes to the actual usage of your VZW device there isn't a whole lot out there that can show you how you are consuming your data plan.  Some monitor applications and devices can be setup ahead of time, but all they are good for is reviewing the data that flows through them.  Special care must be taken when designing and setting up monitors to make sure you capture everything.  Monitors are generally not user friendly to setup or understand and often require detailed readings of numerous logs to determine where problems are, if the monitor can even capture them at all.
The current best practices for data usage are as follows:
1. Power down your VZW device when it is not being used
2. Secure your VZW device with a custom SSID, WiFi and Admin password
- This should be in compliance with security best practices for strong passwords
- A good site to reference is https://howsecureismypassword.net/
3. Take care to disable and shutdown any automatic updates on your devices
4. Be cautious to view and download audio/video content on low resolution
In most cases high data usage is not an intentional doing on the users behalf.  It is the background applications and services installed on the connected devices that run rampant and chew up your data plan without your knowledge or consent.