The Adjustments sub-tab is identical to the Assumptions tab.

When an Object or Budget Account is designated for Payroll, Allocations or Contra Allocations, the system will treat the account as a control account and will not offer the Assumptions tab thus crippling direct data entry.

If you choose to allow users to enter discretionary expenses in addition to controlled transactions from payroll or allocations you can go to Manage Objects and check mark the "Adjustments" box to enable an Adjustments tab for data entry.  

Please note that when the "Payroll", "AllocAcct", and or "ContraAlloc" checkboxes are checked on both Manage Objects and Manage Budget Accounts, or only the Manage Budget Accounts, the Assumptions Sub-tab is replaced by the non-editable read-only "Payroll Projection" tab or the "Allocation" tab.

Note if you do not wish to make data entry available for all accounts common to an Object, you can also go to Manage Budget Accounts and turn on the Adjustments checkbox for a particular account only.

If you do not want a particular Budget Account number to be subject to the "Adjustments" Sub-tab, it can be unchecked on Manage Budget Accounts.  Similarly is you only want one Budget Account to have the Adjustments Sub-tab, it can be checked on Manage Budget Accounts and left unchecked on Manage Objects.